Activities
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Start with the initial values of all the sliders, and run the
simulation by pressing the Play button. This is a relatively simple
collision, a perfectly elastic collision between objects of equal
mass. See if you can find the three momentum and the three kinetic
energy values after the collision. Note that you can enter these one
at a time, and use the "Check Answer" button to check each individual
answer.
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Reset the simulation (press the "Reset Simulation" button), and then
set the mass of ball 1 to 3 kg, and the elasticity to 0. This gives
what we call a completely inelastic collision, in which the objects
stick together after the collision. See if you can predict the
answers, for the momentum and kinetic energy afterwards, before
running the simulation.
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Reset the simulation again, and then set the mass of ball 1 to 3 kg.
This should give you an elastic collision between objects with
equal-and-opposite velocities before the collision, and a mass ratio
of 3. This is a special case. See if you can predict the answers, for
the momentum and kinetic energy afterwards, before running the
simulation - make sure you Play it to see the result, though.
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Adjust the sliders several times, running through various combinations
of parameters. Under what conditions is the total momentum conserved
in the collision? Under what conditions is the total kinetic energy
conserved in the collision?
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Finally, try a collision in which the elasticity is 0.5. Using the
momentum conservation equation, and the elasticity equation, you
should be able to solve for the momentum and kinetic energy after the
collision. See if you can do this.