Lab #7: Conservation of Momentum
Theory:
What is momentum? State conservation of momentum and write down equation for two
body head on collision. Write down conservation of kinetic energy equation for two body
head on collision.
Experiment:
In this exercise, you will start with one car being stationary and toward second car. There
are no external forces acting on those and conservation of momentum can be applied.
1. Adjust MS first. They cannot detect object closer than 40 cm. Place them high
enough and aim in the direction to detect position of the collision carts. MS
measure positive distance away from it.
2. Place car 2 (the one on the right) stationary in the middle of the track and push car
1 (one on the left) toward car 2.
3. When the cars “collide”, car 1 will come to a complete stop, and car 2 will
accelerate to the right.
4. The SF software will give you V vs. t plot for both cars; for car 1 before collision
(initial velocity) and for car 2 after collision (final velocity). Determine the initial
velocity for car 1, Vi and final velocity for car 2, Uf. (NOTE: Ui and Vf are equal
to zero).
5. Measure and record masses of both cars.
6. Calculate total momentum before and after collision and their uncertainties.
7. Calculate total kinetic energy before and after collision and their uncertainties.
8. Is momentum conserved? Is kinetic energy conserved? What can you tell about
the type of collision?