Pasco Scientific ME-6956, Инструкция по эксплуатации и руководство по экспериментам

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012-07558A PAScar Accessory Track Set (2.2 Meter)
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Answers to Questions
1. Momentum is conserved in each case.
2. As shown in this lab, the momentum of each
cart is the same.
3.
4. The lighter car will have a higher kinetic energy.
4. The starting position does not depend on the
car that has the plunger cocked. During the
“ explosion, ” the momentum of the cars is
effected by the fact that the plunger is moving
at a different velocity than either car. How-
ever, since each plunger eventually ends up
moving at the same speed as the car it is on,
there is no difference when the cars are
separated.
Teacher’s Guide
Experiment 1: Conservation of Energy in Explosions
Experiment 2: Conservation of Momentum in Collisions
NOTE:
Without some method of actually
measuring the velocities of cars, this lab should
be only be used for qualitative analysis.
Part I
a. Since the cars have the same mass, they
will exchange velocity in each case.
b. The momentum transfer will be propor-
tional to the ratio of the car masses.
Answers to Questions
1. Each car loses its momentum. The
total momentum is unchanged, because the
total momentum is zero both before and after
the collision.
2. In this case, the total momentum is still
zero both before and after the collision.
KE
2
=
m
1
m
2
KE
1