PASCO SE-8747 Kinesthetics Cart KINESTHESIA-1 - Manual (Page 16)

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Kinesthetics Cart 012-05787C
Experiment 7: Motion in 2-D
“Uniform Motion vs. Accelerated Motion”
The following experiment is a variation of the one described above. A several foot high tripod
carrying an electromagnet is mounted on Kinesthesia-1, and a target is marked on the surface of
the cart directly below the electromagnet. A small ball bearing (1/4”...1/2”) is released from the
magnet and hits the bull’s eye. Now Kinesthesia-1 moves at constant velocity v. Again the steel
ball hits the bull’s eye. Finally, the steel ball is released while the cart is being accelerated. Why
is it that the steel ball no longer hits the bull’s eye?
Only the upper cart is required for this experiment. This is not a kinesthetic experiment. The
Kinesthetics Cart serves only as a large moving platform.
SUGGESTION: In a larger lecture hall or classroom it might be hard to see exactly where
the ball bearing landed on the target. It might, therefore, be advantageous to replace the target
with a typesetter sorting case or similar screw sorting box, where each compartment contains felt,
cotton balls, or another suitable material, to prevent the ball bearing from bouncing into an adja-
cent compartment.
➤ NOTE: The setup shown in Fig. 7-1 will also serve as a demonstration when inertial and non-
inertial frames of reference are being discussed
.
Fig. 7-1: A tripod is mounted on Kinesthesia-1 hold-
ing an electromagnet. A ball bearing is released
directly above a target by remotely switching off the
electromagnet. This experiment is done for v=0,
v=const., a=const., and a=-const.