|
Science Vocabulary Hangman. The computer will randomly pick a term used in science. Discover the word the computer has picked by guessing which letters are in it. Each incorrect guess you make causes the atom man to decay. Solve the puzzle before the atom man completely decays! The question sets include: General Sets, Math, Measurement and Measurement Systems, Atoms and Matter, Force, Motion and Energy, Chemistry, Computer Science, Meteorology and Oceanography, Geology, Astronomy, Biology and Living Systems, The Scientific Method, Individual School Sets. Grades: 2 - 12. http://education.jlab.org/vocabhangman/index.html Science
Crossword Puzzles. Use the clues
provided to solve each crossword puzzle. To place letters on the puzzle,
first select the clue you are answering from the pull-down menu and then
enter you answer in the text box. Press the 'return' key on your keyboard
when you are done. Correct letters will be green while incorrect letters
will be red. Good luck and have fun! Puzzles:
Atoms and Matter, Matter Changing States,
Energy Sources, Energy and Heat Transfer, The Solar System,
Constellations, Life Science, Cell Structures, The Body, Simple Machines,
Scientific Instruments, The Metric System. http://education.jlab.org/sciencecrossword/index.html Who
Wants to Win a Million Dollars? - The Science Game.
Test your knowledge of math and science as you work your way to the
million-dollar level! Although the questions you will answer are real, the
money, unfortunately, is not. Sorry! http://education.jlab.org/million/index.html Science,
Math and Technology Practice Tests. 3rd
grade: Math and Science; 5th grade: Math, Science,
Technology; 8th grade: Math, Science, Technology;
also Chemistry (Scientific Investigation; Nomenclature, Chemical
Formulas and Reactions; Phases of Matter and Kinetic Molecular Theory;
Atomic Structure and Periodic Relationships; Molar Relationships,) Earth
Science (Scientific Investigation, Meteorology, Oceanography and
Groundwater, Astronomy and Space Science, Geology,) Algebra I
(Equations and Inequalities, Expressions and Operations, Relations and
Functions, Statistics,) Algebra II (Equations and Inequalities,
Expressions and Operations, Relations and Functions, Analytical Geometry,
Systems of Equations/Inequalities, Statistical Analysis,) Geometry (Lines
and Angles, Triangles and Logic, Polygons and Circles, Three-Dimensional
Figures, Coordinate Relations, Transformations and Vectors.) 10, 20 and 40
question options. http://education.jlab.org/solquiz/index.html Reading Comprehension Passages. Select one of the passages listed on the page. Complete the passage by selecting the words that best fit the context of the passage. Press the 'Check My Answers!' button when you are done to see how you did! Topics: Charges and Electricity, The Earth's Energy Budget, The Water Cycle, Internet Safety, Looking for Quarks Inside the Atom, Magnets and Electromagnets, Microscopes, Properties and Changes. http://education.jlab.org/reading/index.html
Games Based on the Table
Periodic Table of the
Elements. Point the cursor on the element to find basic information
about it, click on the element to get more information, use "show all
data" button in the upper right corner to get even more advanced
information. Use links below the table and in the bottom of the
page for some specific information. http://www.schoolscience.co.uk/periodic
table.html More good Periodic Table links: http://jcrystal.com/steffenweber/JAVA/jpt/jpt.html
(applet) http://education.jlab.org/itselemental/ http://chemistry.about.com/library/blper5.htm Element
Flash Cards. The computer will give
you an element and you have to supply either its chemical name, its
chemical symbol or its atomic number. Press the 'Check my answer' button
after you have entered your answer. http://education.jlab.org/elementflashcards/index.html Element
Math Game. The computer will randomly
pick an element and present you with that element's data from the Periodic
Table of Elements. Use that information to answer the question that the
computer asks about the number of protons, neutrons, electrons or nucleons
(particles in the nucleus) that an atom of that element contains. Press
the 'Check my answer' button after you have entered your answer. http://education.jlab.org/elementmath/index.html Element
Crossword Puzzles. 1. It's a Gas!; 2. Chemical Symbols
of Elements (easy); 3. Chemical Symbols of Elements (strange); 4 Known
to the Ancients...; 5. The Alkali Metals; 6. The Alkaline Earth Metals; 7.
The Chalcogen Group; 8. The Halogen Group; The Noble Gases.
Use the clues provided to solve each crossword puzzle. To place
letters on the puzzle, first select the clue you are answering from the
pull-down menu and then enter you answer in the text box. Press the
'return' key on your keyboard when you are done. Correct letters will be
green while incorrect letters will be red. Good luck and have fun! http://education.jlab.org/elementcrossword/index.html Element Hangman. The computer will randomly pick the name of one of the elements. Use the clue to discover which element the computer picked. Be careful! Each incorrect letter you guess causes the atom man to decay. Find the element's name before the atom man decays completely! http://education.jlab.org/elementhangman/index.html Element Matching. The computer will give you a list of chemical symbols and a list of chemical names. Choose the chemical name that each chemical symbol represents. Press the 'Check my answers!' button after you have made your choices. http://education.jlab.org/elementmatching/index.html Element Concentration. The computer will display a number of cards with the names and symbols of the elements. After you have had time to study the cards, the computer will flip them over and ask you to find a particular element. Click on the card that contains that element. http://education.jlab.org/elementconcentration/index.html
Mistakes
and Errors in Math and Science Education, Textbooks Errors
Your Sky, the
interactive planetarium of the Web
Beautiful
Demo. View the Milky Way at 10 million light years from the Earth.
Then move through space towards the Earth in successive orders of
magnitude until you reach a tall oak tree just outside the buildings of
the National High Magnetic Field Laboratory in Tallahassee, Florida. After
that, begin to move from the actual size of a leaf into a microscopic
world that reveals leaf cell walls, the cell nucleus, chromatin, DNA and
finally, into the subatomic universe of electrons and protons.
This web page is designed to give everyone an idea
of what our universe actually looks like. There are nine main maps on this
web page, each one approximately ten times the scale of the previous one.
The first map shows the nearest stars and then the other maps slowly
expand out until we have reached the scale of the entire visible universe.
The universe has been
partially mapped out to about 2 billion light years. Here is a map showing
many of the major superclusters within 2 billion light years. Observe a map of the
Cosmic Microwave Background Radiation. Enjoy the most famous
Hubble Space Telescope astronomy pictures of modern times - the Hubble
Deep Field Image. Almost every object in those image is a galaxy typically
lying 5 to 10 billion light years away. A
Sense of Scale. A Visual Comparison of Various Distances
PhET Applets
|
| Vector Addition Two vectors can be added using the triangle or parallelogram method. |
| Vector Addition and Subtraction Two vectors can be added or subtracted. |
| Vector Components The horizontal and vertical components of any vector can be shown. |
| Vector Addition and Subtraction Practice Practice vector addition and subtraction. |
| Uniform Acceleration in One Dimension: Motion Graphs This simulation is intended to help students get a better understanding of the relationships between various quantities involved in uniformly accelerated motion. By adjusting the sliders (or input boxes), a student can change the initial position, the initial velocity, and the acceleration of an object, and can observe how each change affects the graphs of position, velocity, and acceleration vs. time. |
| Position, Velocity, and Acceleration vs. Time Graphs In this simulation you adjust the shape of a Velocity vs. Time graph by sliding points up or down. The corresponding Position vs. Time and Acceleration vs. Time graphs will adjust automatically to match the motion shown in the Velocity vs. Time graph. |
| Kinematics Graphs: Adjust the Acceleration This is a simulation that shows the position vs. time, velocity vs. time, and acceleration vs. time graphs for an object. Students can adjust the initial position and initial velocity of the objects, and then adjust the acceleration of the object during the four time intervals represented on all the graphs. |
| 1D Kinematics: Velocity vs. Time Graphs This simulation shows the velocity vs. time graph for an object moving along a straight line. Adjust the velocities by sliding the blue points up or down. Adjust the total time interval by sliding the red dots horizontally. |
| Uniform Acceleration in One Dimension This is a simulation of the motion of a car undergoing uniform acceleration. The initial position, initial velocity, and acceleration of the car can be adjusted. |
| Kinematics in One Dimension: Two Object System This is a simulation of two cars moving in one dimension. You can adjust the initial position, initial velocity, and acceleration of each of the cars. When the run button is pressed, you can watch an animation of the motion of the cars and also see the position vs. time graph for each of the cars. |
| Projectile Motion Explore projectile motion by changing the initial conditions and watching the resulting changes in the projectile's motion. |
| Exploring Projectile Motion Concepts Using this simulation, students can explore various types of projectile motion. Four projectiles are launched over level ground at angles of 20, 30, 45, and 60 degrees. You have the option of setting them all to have the same horizontal range, the same maximum height, or the same initial velocity. The student can then answer conceptual questions about the time in air, and initial horizontal and vertical velocity and the initial speed. |
| Projectile Motion: Tranquilize the Monkey There is a monkey hanging from a tree branch. Your goal is to shoot the monkey (with a tranquilizer dart, of course - no monkeys were harmed in the making of this simulation). The only problem is that the monkey will let go of the branch at the moment you fire the tranquilizer gun. You must decide where to aim, knowing that the monkey will be falling when the dart hits him. The dart must hit the little white circle on the monkey's back for you to succeed. |
| Relative Velocity: Boat Crossing a River This is a simulation intended to help students grasp the concepts of relative velocity and vector addition. |
This
simulation shows a simple pendulum operating under gravity. For small
oscillations the pendulum is linear, but it is non-linear for larger
oscillations. You can change parameters in the simulation such as mass,
gravity, and friction (damping). You can drag the pendulum with your mouse
to change the starting position. Observe multiple graphs.
2-Dimensional Spring
This
simulation shows a single mass on a spring, which is connected to the
ceiling. The mass is able to move in 2 dimensions, and gravity operates.
Does the motion look random to you? Watch the graph for a while and you'll
see it’s actually an intricate pattern. You can change parameters in the
simulation such as gravity, mass, spring stiffness, and friction
(damping). You can drag the mass with your mouse to change the starting
position. Observe multiple graphs.
Double Pendulum
This
is a simulation of a double pendulum. For large motions it is a chaotic
system, but for small motions it is a simple linear system. You can change
parameters in the simulation such as mass, gravity, and length of rods
(enable the "show controls" checkbox). You can drag the pendulum
with your mouse to change the starting position. Observe multiple graphs.
In
this simulation there is a cart moving along a horizontal track. From the
cart a pendulum is suspended. A spring connects the cart to a wall.
Friction acts on the cart and on the pendulum. You can change parameters
such as gravity, mass, pendulum length, spring stiffness, and friction
(damping). You can drag the cart or pendulum with your mouse to change the
starting position. Click the "reset" button to start from a
resting position. Observe multiple graphs.
Colliding
Blocks(Collisions
and Conservation of Momentum)
This
simulation shows two blocks moving along a track and colliding with each
other and the walls. One spring is attached to the wall with a spring. Try
changing the mass of the blocks to see if the collisions happen correctly.
You can change parameters such as mass, spring stiffness, and friction
(damping). You can drag either block with your mouse to change the
starting positions.
Rigid Body Collisions
This
simulation shows rectangular objects colliding in 2 dimensions. Click near
an object to exert a rubber band force with your mouse. With the keyboard
you can control four "thrusters". The keys S,D,F,E control the
blue object. The keys J,K,L,I (and also the arrow keys) control the green
object. You can also set gravity, elasticity (bounciness), and damping
(friction). You can choose from one to six objects. The mass of the green
object is adjustable (the others are set to mass 1.0).
Work
Done by a Constant and a Variable Force
Did
you ever wonder how to solve for the motion with a curved surface? The
forces are changing as the slope changes. So the math gets a bit more
interesting! You can change the track shape by clicking a button below.
You can change parameters such as gravity or damping. You can drag the
ball with your mouse to change the starting position. Observe multiple
graphs.
This
simulation shows a ball on a roller coaster where the ball can jump off
the track. When the ball is on the track, it is colored blue; when in free
flight it is colored red. The spring is activated when the spring
stiffness is non-zero, which you can change by clicking show
controls. Clicking the spring on or spring
off buttons also changes the spring stiffness. You can change
parameters such as gravity or damping. Drag the ball with your mouse to
change the starting position.
Forces
| Friction: Pulling a Box on a Horizontal Surface This is a simulation of a box being pulled along a horizontal surface by a rope. Students can use the simulation to explore the effects of static and kinetic friction and their relationship to the normal force of the surface. |
| Static and Kinetic Friction on an Inclined Plane This is a simulation of a box being pulled along a horizontal surface by a rope. Students can use the simulation to explore the effects of static and kinetic friction and their relationship to the normal force of the surface. |
| Atwood's Machine / Atwood's Incline This is a simulation of two objects attached to each other with a massless string. The string passes over a massless, frictionless pulley. Use the "Run" button to start the simulation, the "Pause" button to pause it, and the "Reset" button to reset the time back to zero. Use the sliders to adjust the masses of the two objects, the angle of the incline, and the coefficient of friction between mass m2 and the incline (in the simulation it is assumed that the static and kinetic friction coefficients have the same value). Use the checkboxes to show or hide the numerical values and the free body diagrams for the two objects. |
| The Conical Pendulum This is a simulation of a conical pendulum. A conical pendulum consists of an object attached to a string and moving in a horizontal circle. The string length in the simulation is fixed, adjust the radius, animation speed, and view angle with the sliders. |
| Conical Pendulum: 3D This is a 3D simulation of a conical pendulum. A conical pendulum consists of an object attached to a string and moving in a horizontal circle. Adjust the string length, velocity, animation speed, and view angle. |
| Elliptical Orbits & Kepler's 2nd Law This is a simulation of a planet orbiting a sun. Initial conditions can be adjusted. Use the sliders to adjust the initial speed of the planet, the initial distance from the center of the planet to the center of the sun, and the mass of the sun. Hit run to see the orbit animate. The orbit will be with elliptical, circular, parabolic, or hyperbolic, depending on the initial conditions. Show the Kepler's 2nd Law of planetary motion trace to see the elliptical orbit broken into eight wedges of equal area, each swept out in equal times. |
Conservation
| Conservation of Mechanical Energy: Mass on a Vertical Spring This is a simulation showing a mass oscillating on the end of a spring. The kinetic energy, gravitational and elastic potential energies are shown in bar graph form. Adjust the mass and the spring constant, then hit the RUN button. Observe the various forms of energy using the bar graphs. |
| Momentum & Energy: Elastic and Inelastic Collisions This is a simulation of a collision in one dimension between two masses initially sliding toward each other on a frictionless surface. Explore conservation of energy and momentum, as well as elasticity and relative velocity. Adjust the initial velocities, masses of the boxes, and elasticity with the sliders. Use the buttons to run, pause, and reset the simulation. |
| Momentum & Energy: Explosive Collisions This is a simulation of two masses initially sliding or stationary on a frictionless surface with an explosive charge between them. Explore conservation of energy and momentum. Adjust the initial velocity, masses of the boxes, and explosive energy with the sliders. Use the buttons to run, pause, and reset the simulation. |
| The Ballistic Pendulum This is a simulation of a ballistic pendulum. A ballistic pendulum is a device used to determine the speed of a bullet. Follow the instructions below the simulation window. |
| Ballistic Pendulum "Quiz" Same as the simulation above, except the initial velocity is not shown - it must be determined by the user. |
| Dropping a Mass on Another Oscillating Mass This is a simulation of a mass oscillating on the end of a spring, which then has another mass dropped onto it. You can choose to have the mass drop when the oscillating mass is at its equilibrium position or at its maximum displacement from the equilibrium. You can also use the slider to adjust the mass of the object being dropped. Watch how the amplitude and period of the oscillation change when the mass is dropped. Also look for the effect on the total mechanical energy of the mass-spring system. Think about the differences between the situation where the mass is dropped at the equilibrium position vs. when it is dropped at the maximum displacement from the equilibrium. |
| Center of Mass: Person on a Floating Raft This is a simulation of a person walking on a floating raft. Use the sliders to adjust the mass of the raft, the mass of the person, and the animation speed. Use the buttons to start, pause, or reset the animation. |
Rotation
| Rolling Motion Basics + Cycloids This is a simulation of rolling motion. Students can see the cycloid shape traced out by a point on as rolling object and explore the nature of the point's velocity. |
| Rotation, Sliding, Rolling, and Friction Simulation of rolling with and without slipping. Users can change the type of object (solid sphere, solid cylinder, etc.), the mass, the radius, the coefficient of friction, and the initial velocity. You can view a realistic animation of the rolling with slipping and watch as it changes to pure rolling without slipping. |
| Rotation: Rolling Motion In this simulation, the user can explore the rolling motion of various objects. Use the check boxes to select one or more objects. Use the mass and radius sliders to adjust the mass and radius of the object(s). Use the Incline Angle slider to adjust the angle of the incline. Use the Run, Pause, and Reset buttons to control the animation, and the speed slider to adjust the animation speed. |
| Moment of Inertia: Rolling and Sliding Down an Incline This is a simulation of five objects on an inclined plane. The cube slides without friction, the other objects roll without slipping. The different mass distributions cause the rolling objects to have different rotational inertia, so they roll down the incline with different accelerations. |
| Rotational Inertia and Torque This is a simulation of a circular object mounted on an axis through its center with a constant torque applied. Objects with varying rotational inertia (solid sphere, spherical shell, solid cylinder, cylindrical shell) can be chosen, and the mass and radius of the object can be adjusted. |
| Rotational Inertia Lab (choice of three scenarios) This simulation is actually three simulations in one. Students can experiment with a rotating object with various forces applied to it. They can choose a single constant force, a tension force caused by a single falling mass, or an at wood's machine type situation with two hanging masses. Many factors can be adjusted, including all masses, the radius of the rotating object, and the mass distribution of the rotating object. |
| Equilibrium Problem: Bar Supported by Cable This is an adjustable equilibrium problem involving a uniform bar with a mass on it. The bar has an axis at its left end and is supported at its right end by a cable. The mass of the bar and box, the length of the bar, the position of the box and the angle of the cable can all be adjusted. Use the given quantities to determine the tension in the cable. Check your free body diagram, equations, and your determined tension. |
| Angular Momentum Collision This is a simulation involving a ball of clay that is thrown at a thin vertical bar with an axis at its top end. The ball collides with and sticks to the bar, and the bar begins to rotate. |
| Shooting Bullets Vertically Upward into Two Wood Blocks This is a simulation of two identical guns firing bullets vertically upward into identical wood blocks. One gun fires directly into the center of mass of the wood block, the other gun can shoot anywhere into the block. So, one block rises without spinning, the other one spins as it rises. Which block will rise higher after being shot? |
| Angular Momentum: Person on Rotating Platform This is a simulation of a rotating solid cylindrical platform with a person on top. Adjust the mass of the platform and person, and the radius of the platform and the person's path, to see how these changes affect the angular velocity of the system and the centripetal force needed to hold the person on the platform. |
Molecule
Model
These
simulations shows 2, 3, 4, 5 or 6 masses connected springs and free to
move in 2 dimensions. You can change parameters in the simulation such as
gravity, mass, spring stiffness, and friction (damping). You can drag any
mass with your mouse to change the starting position. Click the
corresponding buttons for various combinations of parameter settings. Can
you find all the stable configurations?
http://www.myphysicslab.com/molecule2.html
http://www.myphysicslab.com/molecule3.html
http://www.myphysicslab.com/molecule4.html
http://www.myphysicslab.com/molecule5.html
http://www.myphysicslab.com/molecule6.html
Gas
Molecules Simulation Applet. Demonstrates
the kinetic theory of gases.
This applet is a
simulation that demonstrates the kinetic theory of gases. The color of
each molecule indicates the amount of kinetic energy it has. The applet
may seem very slow on some platforms, far too fast on others. Press
"Reset" to reset the positions and velocities of the molecules
to random values. Pressing "Reset to Equal" will cause the
velocities to all be the same, although they won't stay that way for long.
"Reset to Extreme" will reset half the molecules to a single
large velocity and the other half to a small velocity; again, they won't
stay that way for more than a fraction of a second. "Set Wall
Temp" will set the temperature of the walls to be the same as that of
the heater. The volume slider controls the volume of the container. The
Heater Temperature slider controls the heater at the bottom of the screen;
if the temperature is high, the heater is more likely to give a large
kinetic energy boost to molecules that hit it. If the temperature is low,
the heater becomes a refrigerator; it removes kinetic energy from the
system. The gravity slider controls gravity. At the bottom of the screen
is a velocity histogram showing the distribution of velocities of the
molecules. Again, color is used to indicate velocity; velocities increase
as you go to the right on the graph. The height of the velocity bars shows
the number of molecules that have that velocity. The scale of the graph
changes constantly so watch the colors to orient yourself. The behavior of
the molecules when the volume of gas is diminished is not realistic, of
course. This applet badly needs updating.
Here
is a demonstration of the flow of a vector field. You may choose a vector
field from the pull down menu. In the graphing area, select a rectangular
region by clicking and dragging. When you release, you will see how the
rectangle moves under the flow.
The
change in the area of the rectangle is described by the divergence of the
vector field while the rotation of the sides is described by the curl.
http://www.sunsite.ubc.ca/LivingMathematics/V001N01/UBCExamples/Flow/flow.html
| Buoyancy Buoyancy simulation. Use the sliders to adjust the density of the fluid, the density of the object, and the viscosity of the fluid. Press the "Run" button to start or resume the animation, the "Pause" button to pause the animation, and the "Reset" button to reset the simulation to its initial values. Sliders can be adjusted as the animation runs. |
| Fluid Dynamics and the Bernoulli Equation This is a simulation made to help students get an understanding of the Bernoulli equation for flowing fluids. This is a simulation of an incompressible fluid flowing from left to right through a pipe. In the simulation you can adjust the height, pressure, velocity, and radius of the pipe for the fluid flowing in the left side of the pipe. You can also adjust the height and radius of the right side of the pipe. The velocity and the pressure in the right side of the pipe can be calculated using the Bernoulli equation. After they have been calculated, they answers can be checked by marking the checkbox in the top right corner of the simulation. |
Simple Harmonic Motion.
Extend or compress the spring (by dragging the mass on the end of the
spring) and let go. When you
let go, you will see the resulting cosine curve. Change the spring
constant (k). How does this change the motion? How does this change
the cosine function? What is the relationship between k and the
frequency? What is the relationship between the mass m, the
frequency and the amplitude?
http://www.intmath.com/TrigGrph/5_ApTG.php
This
simulation shows a single mass on a spring, which is connected to a wall.
This is an example of a simple linear oscillator. You can change
parameters in the simulation such as mass, spring stiffness, and friction
(damping). You can drag the mass with your mouse to change the starting
position. Observe energy balance and multiple graphs.
http://www.myphysicslab.com/spring1.html
Double
Spring
This
simulation shows two springs and masses connected to a wall. If you've
ever played with an oscilloscope you've probably seen curves like these.
They are called Lissajous curves and are generated by simple sine and
cosine functions. You can change parameters in the simulation such as mass
or spring stiffness. You can drag either mass with your mouse to set the
starting position. Observe multiple graphs.
http://www.myphysicslab.com/dbl_spring1.html
Coupled
Oscillations. We have two springs
with different sized masses connected and hanging vertically. While
holding the top mass still, we pull down the bottom mass. Then we let go
of both masses and allow the system to move freely. A motion sensor is
connected to a computer and we can see the resulting movement of the
masses as time progresses. In this Flash interactive, you can reset the
motion at any time and get a different set of resulting graphs. Just click
on the round button at the bottom.
http://www.intmath.com/TrigGrph/6_CoTa.php#dubsprings
Two
mass-spring oscillators are coupled together by a stretchy cord.
http://www.kettering.edu/~drussell/Demos/coupled/coupled.html
Oscillations
Simple Harmonic Motion animation relating SHM to uniform circular motion.
Coupled
Oscillations. Demo.
This java applet is a simulation that
demonstrates the motion of oscillators coupled by springs. The oscillators
(the "loads") are arranged in a line connected by springs to
each other and to supports on the left and right ends. The mass of each
load and the stiffness (spring constant) of each spring can be adjusted.
At the top of the applet on the left you will see the string of
oscillators in motion. By default, the number of loads is set to 5. To
move the loads, click on one of them, drag it slightly to one side and
then release it. Below the string you will see a graph showing each normal
mode's contribution to the motion. There are two sets of terms; on top are
the magnitude terms, which shows the amplitude of each normal mode, and on
the bottom are the phase terms. Low-frequency modes are on the left and
high-frequency modes are on the right. If you move the mouse over one of
the modes, it will turn yellow, and the motion of the corresponding mode
will be drawn underneath the line of oscillators in yellow (unless it's
too small to see). So if you move the mouse over all the modes, you can
see each of the terms individually. (One thing to keep in mind when
looking at the magnitude of each mode is that the scale is not linear. If
it were linear, it would look like the higher-frequency modes all had zero
magnitude because their contribution is so small. For small magnitudes,
the scale is logarithmic; then about 1/4 of the way up the scale it
switches to linear. The same is true for negative magnitudes.) You can
modify the motion of the string in one of two ways. You can click on it
directly, or you can modify the normal modes. The Setup popup
allows you to view some predefined interesting cases. The first two
choices, 5 masses and 2 masses are very simple. The next two
demonstrate weak coupling; in both cases, you will see that the load on
the right will oscillate for a while, and then stop; meanwhile the one on
the left will oscillate, and then will stop while the right one
oscillates, etc. This is because the two active modes have frequencies
that are very close, causing beats to occur. Another way to look at it is
that energy is slowly transfered from the left load to the right and then
back again. The Mouse popup controls what happens when you click on
the string. The default setting is Pull string, which causes the
load you click on to be pulled to either side. If you set the popup to Move
load, you can edit the position of a single load without disturbing
the others (until you release the mouse button). If you set it to Modify
masses, you can modify the mass of one of the loads by clicking on it
and dragging the mouse up or down. The size of the load will be changed to
match its mass. If you set it to Modify springs, you can modify the
spring constant of one of the springs by clicking and dragging up or down.
Springs with a high spring constant have a reddish color. The Reset
Positions button allows you to reset the positions of all the loads to
equilibrium. The Reset Masses button allows you to reset the masses
of all the loads to the default. The Reset Springs button allows
you to reset the springs to the same spring constant. The Stopped
checkbox allows you to stop or start the simulation. Occasionally two
loads will collide, or one of the loads will hit the edge. If this
happens, the loads involved will turn red briefly, and the normal modes
will be changed to match the new motion of the string. By default, the
loads will collide inelastically, causing them to move at the same
velocity until they are pulled apart by springs. The Elastic Collisions
checkbox allows you to change this so that they collide elastically. When
the Lissajous Figures checkbox is checked, and there are two loads
(or two active modes), then the amplitudes of these modes (their normal
coordinates) will be plotted, producing a Lissajous figure. This makes the
most sense for cases of weak coupling. The Damping slider controls
how much damping there is. Damping is a force that slows the string down.
It is proportional to the speed of the string, so high-frequency modes are
damped more than lower ones. The Number of Loads slider will adjust
the number of loads on the string. This can be set as low as one. If you
reduce the number of loads then you also reduce the number of normal
modes.
http://www.falstad.com/coupled/
This
simulation shows a dangling stick, which is a massless rigid stick with a
point mass on each end. One end of the stick is attached to a spring, and
gravity acts. Click "show controls" and then you can change
parameters in the simulation such as mass, gravity, and damping. You can
drag either end of the stick with your mouse to change the starting
position. The "reset" button puts the simulation in a motionless
equilibrium. Scroll down to see the math!
http://www.myphysicslab.com/dangle_stick.html
Oscillating
Membrane Demo.This java applet is a
simulation of waves in a rectangular membrane (like a drum head, except
rectangular), showing its various vibrational modes. To get started,
double-click on one of the grid squares to select a mode (the fundamental
mode is in the upper left). You can select any mode, or you can click once
on multiple squares to combine modes. Also try clicking on the membrane
itself and dragging up or down. Click "Full Directions" for detailed
directions.
http://www.falstad.com/membrane/
or http://www.falstad.com/membrane/j2/
Lissajous
(pronounced LEE-suh-zhoo) figures were discovered by the French
physicist Jules Antoine Lissajous. He would use sounds of different
frequencies to vibrate a mirror. A beam of light reflected from the mirror
would trace patterns which depended on the frequencies of the sounds.
Lissajous' setup was similar to the apparatus which is used today to
project laser light shows. Before the days of digital frequency meters and
phase-locked loops, Lissajous figures were used to determine the
frequencies of sounds or radio signals. A signal of known frequency was
applied to the horizontal axis of an oscilloscope, and the signal to be
measured was applied to the vertical axis. The resulting pattern was a
function of the ratio of the two frequencies. Lissajous figures often
appeared as props in science fiction movies made during the 1950's. One of
the best examples can be found in the opening sequence of The Outer
Limits TV series. ("Do not attempt to adjust your picture--we
are controlling the transmission.") The pattern of criss-cross lines
is actually a Lissajous figure. The Lissajous Lab provides you with a
virtual oscilloscope which you can use to generate these patterns. (You
will control the horizontal. You will control the vertical.) The
applet also allows you to apply a signal to modulate the hue of the trace,
so you can create colorful designs.
http://www.math.com/students/wonders/lissajous/lissajous.html
http://www.falstad.com/loadedstring. Demo.
This java applet is a simulation that demonstrates standing
waves on a vibrating string (a loaded string, to be precise). To set
the string in motion, click "Center Pluck" or
"Fundamental", or click on the string.
Below
the string you will see a graph showing each normal mode's contribution to
the string's vibration. There are two sets of bars; on top are the
magnitude bars, which shows the amplitude of each normal mode. These bars
can be adjusted with the mouse, or you could double-click on one to
isolate a particular mode.
http://www.falstad.com/loadedstring/
2-D
Waves Applet. Demo. This java applet
is a simulation that demonstrates scalar waves (such as sound waves) in
two dimensions. It demonstrates the wave principles behind slit
diffraction, zone plates, and holograms. To get started with the applet,
just go through the items in the Setup menu in the upper right. Click "Full
Directions" for detailed directions.
http://www.falstad.com/wave2d/
3-D
Waves Applet. Demo. This java applet
is a simulation that demonstrates scalar waves (such as sound waves) in
three dimensions. It shows point sources, line sources, and plane waves,
and also demonstrates interference between sources. When the applet starts
up you will see red and green waves emanating from two sources in the
center of a cubic box. The wave color indicates the acoustic pressure. The
green areas are negative and the red areas are positive. Rotate the box
with the mouse to view it from different angles. To get started with the
applet, just go through the items in the Setup menu in the upper right.
Click "Full Directions" for detailed directions.
http://www.falstad.com/wavebox/
| Simple Harmonic Motion, Circular Motion, and Transverse Waves This simulation is an exploration of the relationships between Simple Harmonic Motion, Uniform Circular Motion, and Transverse Wave Motion. |
| Simple Harmonic Motion: Mass on a Spring This simulation shows the oscillation of a box attached to a spring. Adjust the initial position of the box, the mass of the box, and the spring constant. Use the Run, Pause, Reset, and Step buttons to examine the animation. Check or uncheck boxes to view/hide various information. |
| Oscillation Graphs Quiz In this "quiz" you will be shown a motion graph for an oscillating object. It can be a position, velocity, acceleration, or net force graph - each graph is vs. time. From four other graphs of a different aspect of the object's motion, you must choose the one that matches the motion shown in the original graph. After you check you answer you can create a new randomly selected graph and try again, over and over. |
| Simple Harmonic Motion Tutorial This is a multi-step tutorial on Simple Harmonic Motion, showing derivations of the equations for position, velocity, acceleration, and period of an object in simple harmonic motion. |
| Waves Tutorial This is a multi-page tutorial on the basics of mechanical waves. It incorporates many of the simulations listed separately in this menu, but also includes many animations and a lot of general information about waves. Each page has links at the bottom that lead you to the next (or previous) page in the tutorial. |
| Wave Pulse Interference and Superposition This simulation allows students to observe the superposition of two wave pulses of varying height and width. This is an animated simulation of the superposition of two waves pulses. The sliders can be used to change the height and width of the pulses, as well as the animation speed. Use the buttons to start or stop the animation. |
| Wave Pulse Interference and Superposition 2 This is a simulation of two wave pulses moving along the same string in opposite directions. When the two pulses overlap, their sum is shown on the bottom black string. The sum at any given point along the string is simply the sum of the displacements from equilibrium of each of the individual pulses at that point. This is called the principle of superposition. |
| Wave Pulse Superposition Practice This is a simulation of the interference of two wave pulses on a string. Choose the shapes of the pulses either by manually moving the orange and blue points up or down or by selecting from the gallery of pre-set pulse shapes on the right. To practice pulse addition, uncheck the "Choose Pulse Sum" check box, and select the "Draw Your Own" checkbox. Move the pulses manually so that they partially or completely overlap. Now move the green points to make your prediction of the shape of the sum of the two pulses. When you think you have the correct shape, choose "Show Pulse Sum" to see if you were correct. Note: the green dots can be moved left and right as well as up and down. |
| Superposition of Transverse Waves Simulation of the superposition of two waves moving in the same medium. |
| Longitudinal Waves Animated longitudinal travelling and standing waves. |
| Longitudinal and Transverse Wave Basics This simulation shows standing waves both on strings and in open and closed air columns. Use the buttons to choose waves on a string or waves in air columns, as well as the particular harmonic. Use the check boxes to show or hide the transverse and longitudinal displacement waves, as well as the pressure variation wave. |
| Standing Waves This is a simulation of two cars moving in one dimension. You can adjust the initial position, initial velocity, and acceleration of each of the cars. When the run button is pressed, you can watch an animation of the motion of the cars and also see the position vs. time graph for each of the cars. |
| Standing Waves on Strings Simulation of standing waves on strings. Use the sliders to adjust the vibrational frequency, the linear density of the string, and the string tension. |
| Wave Pulse Reflection (Free & Fixed Ends) This is a simulation of a wave pulse bouncing off the end of a string. The string's end can be fixed or free, and there are options for showing the undisturbed incident and reflected waves. |
| Air Column Resonance This simulation is intended to show how the process of sound wave resonance in air columns works. |
| Air Column Resonance with Longitudinal Waves This is a another simulation of sound wave interference in air columns. This version of the simulation allows you to look at the longitudinal version of the first two standing waves. As with their transverse counterparts, when these two longitudinal waves align perfectly, resonance occurs. Adjust the slider to find the various resonances and look for the relationship between the length of the tube and the wavelength of the wave. Note that this relationship depends on whether the far end of the tube is open or closed. |
| The Doppler Effect & Sonic Boom Explore the Doppler Effect for sound and Sonic Boom. Use the sliders to adjust the speed of the sound source and the sound observer. |
| Surface Wave Interference in 3D This is a 3D simulation showing the interference of surface waves (like waves on water). View from various angles and adjust the frequency, amplitude and distance between the two wave sources. |
| Surface Waves This is a simulation of a surface wave. Use the sliders to adjust the amplitude, wavelength, and speed of the wave. Use the checkbox to show that the particle motion in the wave is circular. |
http://www.cs.ubc.ca/spider/kvdoel/sound_demo6.html
The
Doppler Effect: Source
Adjust
the slider to change the speed of the police car. (Watch for details in
the background that change on each pass....)
http://www.colorado.edu/physics/2000/applets/doppler.html
Box
Modes Applet: acoustic
standing waves in a 3-d box.
At
the top of the applet on the left you will see the box, oscillating in its
fundamental mode. Below the box you will see a series of grids showing
each normal mode's contribution to the vibration. In each grid, the modes
are laid out in the following order:
|
0,0,p |
1,0,p |
2,0,p |
... |
|
0,1,p |
1,1,p |
2,1,p |
... |
|
0,2,p |
1,2,p |
2,2,p |
... |
|
... |
... |
... |
... |
and
each grid has a different value of p, as shown below:
|
p=0 |
p=1 |
p=2 |
p=3 |
|
p=4 |
p=5 |
p=6 |
p=7 |
So
for example, the top left corner in the top left grid is the 0,0,0 mode,
and the top left corner in the bottom right grid is the 0,0,7 mode.
The
notation m,n,p refers to the mode having an acoustic pressure
proportional to cos(mx)cos(ny)cos(pz), where x ranges
from 0 to pi. Each element of the grid has a color which indicates the
presence or absence of the mode it represents. Black means the mode is not
present; green means the mode is present with a positive coefficient, and
red means it is present with a negative coefficient. In addition, each
mode may have a phase shift, which indicates that its oscillatory cycle
leads or lags the others. This is indicated by a blue line (see details on
the web page).
http://www.falstad.com/modebox/
Light
Image Formation with Convext Lenses
| Light Mixing Mix colors of light with adjustable brightness. Drag the circles to experiment with mixing colors of light. Use the sliders to change the light intensities. |
| Color Pigment Mixing Mix colors of light with adjustable brightness. Drag the circles to experiment with mixing colors of light. Use the sliders to change the light intensities. |
| Polarization of Light This is a simulation intended to help visualize polarization. A polarizing filter has a particular transmission axis and only allows light waves aligned with that axis to pass through. In this simulation unpolarized waves pass through a vertical slit, leaving only their vertical components. This vertical transverse wave approaches a vertical slit. If the slit is rotated, only a component of the wave can pass through. If the slit is rotated 90 degrees, the wave is stopped completely. |
| Double Slit Diffraction and Interference This is a simulation of light being diffracted by a double slit, intended for anyone looking to learn about diffraction and interference. Use the sliders to change the wavelength of the light, the distance between the slits, the distance to the screen, and the height of the point where the waves come together on the screen. You can use the checkboxes to choose between dots representing crests or troughs on the red wave, in order to look for constructive or destructive interference |
| Double Slit Interference This is a simulation of diffraction of light by a double slit. Use the sliders to adjust the distance between the slits and the wavelength of the light. Use the checkboxes to show or hide the wavefronts, maxima, and vertical scale. Use the Show Interference Pattern button to create the interference pattern that would be seen on the screen. Note that the distances in the simulation are all very small, so that you can see the wavelength separations. The y distances shown in the scale and the distance from the slits to the screen (L) are proportional, so they can just be thought of as meters or any other convenient unit. |
| Diffraction Grating Laser Lab This is a simulation of a typical laser diffraction lab set up. Examine the set up in the 3D window, it shows a laser, a diffraction grating, and a screen. Use the checkbox to place the grating in front of the laser, and look at the pattern of dots that appear on the screen. Use the sliders to change the distance from the grating to the screen, the number of lines per millimeter in the diffraction grating, and the wavelength of the laser. Use the diagram of the screen in the top window to analyze the numerical positions of the dots on the screen using diffraction equations. |
| Thin Film Interference This is a simulation of thin-film interference. In thin-film interference, light waves reflect of the front and back surfaces of a transparent thin-film. The two primary reflected waves interfere, sometimes constructively. Use the sliders or input boxes to adjust the index of refraction of the material in front of the thin film, the thin film, and the material behind the thin film, as well as the thickness of the thin film and the wavelength of the incoming light. |
| Reflection and Refraction A basic simulation showing refraction and reflection of a light ray. This is a simple simulation showing the reflection and refraction of a ray of light as it attempts to move from one medium to another. Use the sliders to adjust the index of refraction of each of the two materials, as well as the angle of incidence (the angle between the incident ray of light and the normal to the surface). Use the check boxes to show or hide various information. |
| Dispersion of Light Prism color dispersion, ala Pink Floyd. Move the white dot to change the orientation of the incident ray of white light. Use the sliders to adjust the index of refraction of the surrounding materila (n1), the red light index of refraction of the prism (nred), and the percent difference between the index of refraction of the prism for red light and the index of refraction of the prism for violet light (% Difference). |
| Plane Mirrors This is a simulation of image formation in a plane mirror. Move the top or bottom of the red arrow to see the effect on the image. |
| Concave and Convex Mirrors Simulation of image formation in concave and convex mirrors. Move the tip of the Object arrow or the point labeled focus. Move the arrow to the right side of the mirror to get a convex mirror. |
| iPad Spherical Mirror Simulation Concave and Convex Mirror Simulation optomized for use on mobile devices. |
| Concave and Convex Lenses Simulation of image formation in concave and convex lenses. Move the tip of the "Object" arrow to move the object. Move the point named " Focus' " to change the focal length. Move the point named " Focus' " to the right side of the lens to change to a concave lens. |
| Lens Simulation for iPad Concave and Convex Lens Simulation optomized for mobile devices. |
| Lens Refraction and Spherical Aberration Simulation of refraction and spherical aberration for lenses. This simulation shows realistic refraction of parallel rays passing through a convex lens with spherical surfaces. Unlike the Convex and Concave Lenses simulation, where all the bending occurs at the center of the lens and all parallel rays pass exactly through the focus, this simulation uses Snell's law to determine the actual amount of bending at each of the surfaces of the lens. You can adjust the amount of curvature for each side of the lens, the index of refraction of both the lens and the material surrounding the lens, and the zoom level. The fact that the parallel rays do not converge at a single point is due to spherical aberration. |
| Lenses & Chromatic Aberration Simulation showing chromatic aberration of lenses. This simulation shows the bending of red and violet rays from either end of the visible spectrum as it occurs in lenses. Use the sliders to adjust the radii of the spherical lens surfaces and the index of refraction of the lens. Use the buttons to zoom in or out. |
| 2D Image Formation by Lenses This is another simulation showing images formed by concave and convex lenses, but this one shows the images of two dimensional objects. Many lens simulations show the images formed by a simple one dimensional object, typically an arrow. This one allows you to see the images of two dimensional objects. move the circle, triangle and quadrilateral on the left side of the lens, change their size and shape, and watch the images formed on the right side of the lens. Move the point labeled " F' " to change the focal length of the lens. Move " F' " to the right side of the lens to change from a convex to a concave lens. |
| Optics of the Human Eye This is a simulation demonstrating the optics of the human eye. It also shows how various lenses can be used to correct for faulty vision. Be aware that it is a simplified version of what actually happens. In the simulation, there is no bending when light moves from the air into the eye (when most of the actual bending happens). Instead, in the simulation only the bendings that happen in the lens of the eye (or in the corrective lenses) is shown |
| Rainbow Formation This simulation is intended to help students understand some of the phenomena involved during the formation of rainbows. |
| Rainbow Formation in 3D This is a 3D simulation of the processes involved in the formation of a rainbow. |
| AP Physics 2 Refraction Problem This is a simulation based on a problem on the publicly released 2015 AP Physics 2 exam. I used the actual indices of refraction given in the problem, and made the simulation to the same scale as used in the problem. The simulation shows why you see two dots at the bottom of the glass when the original angle of incidence is small enough. It also illustrates why the second dot gets brighter when the critical angle of incidence is reached at the liquid-air interface. The simulation also shows that the part of the problem about why the second dot disappears is misleading. The problem states that the second dot disappears due to total internal reflection, but you can see in the simulation that the second dot would actually disappear due to its ray not hitting the bottom of the glass container long before the critical angle for the glass-liquid interface is reached. |
| Image Formation with Convex Lenses This is an new simulation that can be used to explore image formation using a convex lens. Unlike the other convex lens simulations on this site, it allows you to zoom in and out to adjust the scale, a choice of dark or light background, and a view choice with many rays of light. |
Bohr's
Theory of the Hydrogen Atom
This
applet illustrates a hydrogen atom according to particle or wave model.
You can choose a principal quantum number n. The right part of the
graphics represents the energy levels of the atom. Right down at the
bottom you can read off the orbital radius r and the total energy E.
If
you try to vary the orbit's radius with pressed mouse button, this will
generally lead to a non-stationary state. You can realize that by using
the option "Wave model": The green wavy line which
symbolizes the de Broglie wave will not be closed in most cases. Only if
the circle's circumference is an integer multiple of the wavelength
(blue), you will get a stationary state.
http://www.physics.umd.edu/courses/Phys111/goodman/java/phe/bohrh.htm
Hydrogen Energy Levels
This is a simulation of an atomic energy level diagram of the hydrogen atom.
Contemporary Physics
Special
Relativity. Demo. This applet
demonstrates some physical effects of Einstein's Special Relativity. On
the left is a graph of "space", in each experiment you will see
objects moving through space here. On the right is a space-time diagram of
all the objects and the observer. In general, BLUE = Object, RED =
Observer.
* Choose an experiment using the
pull-down menu.
* Use the scrollbar to adjust the
speed you would like the main object in the experiment to move at.
* Choose the frame you would like to
see using the Switch Frames. The orthogonal axes in the Space-Time diagram
are those of the rest frame's.
* Press START to begin
experimenting.
* Press RESET to be able to restart
a new experiment at a different speed.
* Press Java TA to run through the
lesson for this applet.
http://www.cco.caltech.edu/~phys1/java/phys1/Einstein/Einstein.html
Finding the Speed of Light with Marshmallows
All you will need is a microwave and some marshmallows.
http://www.physics.umd.edu/ripe/icpe/newsletters/n34/marshmal.htm
| Coulomb's Law with Two Charged Objects This is a basic simulation showing the force of attraction or repulsion between two charged objects. The charge on each object and the positions of the objects can be changed. The resulting forces are shown by force vectors, and the numerical magnitude is also shown. |
| The Millikan Oil-Drop Experiment This activity allows students to simulate a simplified version of Robert Millikan's Oil-Drop experiment. Instructions are given under the simulation. |
| Electron Charge to Mass Ratio Lab This is multi-step simulation of the experiment done by J. J. Thomson to determine the charge/mass ration for an electron. |
| Electromagnetic Waves This is a simple animation representing an electromagnetic wave. The green vectors show the fluctuation of the electric field, the red vectors show the fluctuation of the magnetic field. |
| Electric Field & Potential A simulation showing the electric field and electric potential map around a collection of point charges. |
| Electric Circuit with Four Identical Light Bulbs This is a simulation of a combination circuit with a power supply, four identical light bulbs, and three switches. Open and close the switches and make predictions about the amounts of voltage across the bulbs, the currents through the bulbs, and the brightness of the bulbs (which is related the power each is dissipating as heat and light). Use the checkboxes to show or hide the voltages and currents. |
| Capacitor Lab Simulation of a capacitor charging. Use the sliders to adjust the battery voltage, the resistor's resistance, the plate area, and the plate separation. Use the check boxes to open and close the switch, as well as turn the animation on one off. When animation is turned off, you can use the step buttons to advance time forward or backward in small steps. |
| Charged Particle in an Electric Field This is a simulation of a charged particle being shot into a uniform electric field. Use the sliders to adjust the various quantities. Press run to shoot the particle into the field. |
| Charged particle in a Magnetic Field This is a simulation of a charged particle being shot into a magnetic field. It can be used to explore relationships between mass, charge, velocity, magnetic field strength, and the resulting radius of the particle's path within the field. Use the sliders to adjust the particle mass, charge, and initial velocity, as well as the magnetic field strength. |
| Charged Particle in a Magnetic Field 3D This is a 3D simulation of a charged particle moving in a magnetic field. Adjust the strength of the magnetic field, the particle mass, particle charge, and its initial velocity in the x and z directions using the sliders. Hit the RUN button to observe the path of the particle in the magnetic field. |
| Equipotentials & Electric Field of Two Charges In this simulation you can adjust the charge and position of the two charges using the sliders or the input boxes. The sliders work, but do not work smoothly due to the complexity of the calculations - so you may be better off using the input boxes. Choose to view in 3D and the Electric Potential is shows as the third dimension. Choose the equipotential view and you'll see a 2D view with equipotential lines shown. In this view you can also choose to see vectors showing the direction of the electric field. |
| DC Motor In this simulation of a DC motor, you can adjust the voltage, magnetic field, and the number of loops in the coil. |
| Electromagnetic Induction In this simulation a current can be induced in a coil of wire by the motion of a bar magnet. |