PASCO ME-9429B 1.2 m Classic Dynamics System - Manual (Page 13)

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M o d e l N o . M E - 9 4 2 9 A E x p e r i m e n t 2 : C o n s e r v a t i o n o f M o m e n t u m i n C o l l i s i o n s
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Experiment 2: Conservation of Momentum
in Collisions
Purpose
The purpose of this experiment is to qualitatively explore conservation of momentum
for elastic and inelastic collisions.
Theory
When two carts collide with each other, the total momentum of both carts is con-
served regardless of the type of collision.
An elastic collision is one in which the carts bounce off each other with no loss of
kinetic energy. In this experiment, magnetic bumpers are used to minimize the energy
losses due to friction during the collision. In reality, this “elastic” collision is slightly
inelastic.
A completely inelastic collision is one in which the carts hit and stick to each other. In
this experiment, this is accomplished with the hook-and-loop bumpers on the carts.
Part I: Elastic Collisions
Figure 2.1
1. Instal the feet on the track and level it.
2. Orient the two carts on the track so their magnetic bumpers are toward each
other.
3. Test cases A1 through A3 and B1 through B3 described below. Draw two dia-
grams (one for before the collision and one for after the collision) for each case.
In every diagram, show a velocity vector for each cart with a length that approxi-
mately represents the relative speed of the cart.
A. Carts with Equal Mass
Case A1: Place one cart at rest in the middle of the track. Give the other cart an initial
velocity toward the cart at rest.
Required Equipment from Dynamics System
Track with Feet
Plunger Cart
Collision Cart
Other Required Equipment
Paper (for drawing diagrams)