PASCO ME-9429B 1.2 m Classic Dynamics System - Manual (Page 11)

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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 1 : C o n s e r v a t i o n o f M o m e n t u m i n E x p l o s i o n s
11
Experiment 1: Conservation of Momentum
in Explosions
Purpose
The purpose of this experiment is to demonstrate conservation of momentum with
two carts pushing away from each other.
Theory
When two carts push away from each other (and there is no net force on the system),
the total momentum is conserved. If the system is initially at rest, the final momentum
of the two carts must be equal in magnitude and opposite in direction to each other so
the resulting total momentum of the system is zero:
Therefore, the ratio of the final speeds of the carts is equal to the ratio of the masses of
the carts.
To simplify this experiment, the starting point for the carts at rest is chosen so that the
two carts will reach the ends of the track simultaneously. The speed, which is the dis-
tance divided by the time, can be determined by measuring the distance traveled since
the time traveled by each cart is the same.
Thus the ratio of the distances is equal to the ratio of the masses:
Procedure
1. Instal the feet on the track and level it. Install one end stop at each end with the
magnetic sides facing away from the carts.
Required Equipment from Dynamics System
Track with Feet and End Stops
Plunger Cart
Collision Cart
Cart Masses
Other Required Equipment Suggested Model Number
Mass set ME-9348
p m
1
v
1
m
2
v
2
– 0 = =
v
1
v
2
-----
m
1
m
2
------ =
v
1
v
2
-----
x
1
t
---------
 
 
x
2
t
---------
 
 
---------------
x
1
x
2
--------- = =
x
1
x
2
---------
m
1
m
2
------ =