Lindberg's Physlet Code

The following links are to physlet animations of physics ideas that use Wolfgang Christian's Physlets. The activities were coded by Vern Lindberg, and in some cases are adapted from other code as indicated in the individual pages. These run in Netscape Navigator 7 under Mac OSX, and should run on Netscape or Explorer under windows. You are welcome to use or adapt code providing that it is for educational applications--read the physlets information on use and copyright.

1D Kinematics

  1. paths Balls move in different paths. Name paths. (circle, line, parabola)
  2. ave_speed Investigate differences in average and instantaneous speed and velocity. 1. Three balls, same ave velocity= ave speed 2. One ball in round trip.
  3. ave_speed_graph Part 1 (three balls) of previous exercise with x-t graphs added
  4. MotionDiagram_to_graph Watch animation, sketch graph, check with actual plot.
  5. KinematicsCheck Puck off wall again, different conditions, find velocity and speed
  6. 1D Accel A ball heads toward a wall, bounces off and comes to rest due to a friction-like force. Graph of velocity shows two accelerations and sudden change at impact.
  7. 1Dpaths Four balls travel in straight lines with different motions (const v, accelerated uniformly, SHM). Describe motion and determine maximum velocity.
  8. 1DpathsAns Answers including velocity vectors and readout of velocity
  9. SpeedVelocity1 Puck moves at constant speed, bounces off wall, changing speed, questions of velocity and speed.
  10. SpeedVelocity1T Same as above with image of car (Incomplete)
  11. SpeedVelocity2 As above but adding graph of x-t
  12. SpeedVelocity3 As above adding arrow for displacement
  13. a_v_x A ball accelerates. First sketch graph of position-time on screen, then see if it is correct. Next sketch v-t on a second grid and check. Finally sketch a-t and check.
  14. MatchGraphs1D Car moves in several manners. Determine a function that matches motion
  15. MotionDiagram_to_graph Motion is shown, then user sketchs x-t on screen, then checks.
  16. HareAndHound Graphs of x-t cross. When are speeds same etc.
  17. rocket Rocket launched from rest, engine off after 3 s. Shows motion graph
  18. rocketVel Rocket launched from rest, engine off after 3 s. Shows velocity graph
  19. rocketbad Same rocket, second part of trajectory assumes v=0 at engine off point.
  20. rocketbadVel Same rocket, second part of trajectory assumes v=0 at engine off point. Plots velocity.
  21. carshift A car shifts gears smoothly and a graph of x-t is shown. Can you see when the shift occurs?
  22. carshiftvel Same car but now v-t is shown. Shift is now clear with different (constant) values of acceleration before and after.

2D Kinematics

  1. ball 2D Trajectory of ball on another planet, find minimum speed.
  2. ballAns Shows velocity vector and components for previous problem.
  3. circular Uniform Circular Motion, drag vectors to get Δv
  4. path2d Ball moves in an oval with variable speed. Plot of speed-time is shown. Vectors for velocity and acceleration are shown.
  5. nonUniformCircular Ball speeds up going around a circle. Velocity and acceleration observed.


  1. vector1 Two fixed vectors, arrange to get sum, difference
  2. vectors2 Arrange 3 vectors to get sum. Check with components.


  1. 1d_drag Parachutist falling with quadratic air resistance
  2. rocketLaunchTrue Includes effect of fuel, assumes constant g and no drag
  3. ballDrag2D Projectile (not on Earth) with quadratic air drag


  1. ForceWork Apply a constant force for limited time and see how far and how fsat object ends up. After a Beichner exercise.
  2. work_energy_area2 Horizontal mass-spring and graphs. Which one shows the work?

Phasors Both have problems.

  1. phasors Phasor to wave
  2. phasor2 Phasor to wave again