Collisions in 2-dimemsions
This Applet shows the collision between two balls.
The red mass (m1)
moves along and collides with the green mass
(m2) which is initially stationary. The bottom
panel shows the collision as you would normally see it. The top panel shows the collision from a point
of view known as the centre-of-mass. To begin, click off the Show CM check box.
-
The mass ratio (m1/m2) shows the ratio of
the two masses. Initially both have the same mass so the ratio is 1. you
can change the ratio by moving the slider or just typing a number in the
box.
-
The impact parameter defines how far from
the centre of mass m2 the centre of mass m1 hits. If this parameter is
zero we will have a head-on collision. If this parameter is greater than
2 the red mass will miss the green mass. You can change the impact parameter
by typing a number in the box or by clicking on the red ball and draging
it.
-
The collision is assumed to be an elastic collision.
Things to do:
-
One dimensional collisions: Set the impact
parameter to zero.
-
With a mass ratio of 1 and an impact parameter of
zero, observe the collision. Why does the red ball stop after the collision?
-
Increase the mass of the red ball and see what happens.
Can you explain your observations?
-
Two dimentional collisions: Set the impact
parameter to a number between 0 and 2.
-
With the mass ratio set to 1 this is very like a
real world billiard ball collision. Notice that the angle between the paths
of the two balls after the collision is a right angle. Can you see why
this is so?
-
Change the mass ratio and make sure you understand
what you observe in terms of Conservation of Momentum and Conservation
of Energy.
Programming: Drew Dolgert
Owner and contact: Michael Fowler - mf1i@virginia.edu
Date: 22 September 1998
Version: 1.0
Distribution: Gnu Public License
Language: Java 1.1
Details