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Mini-Quiz: Relative Motion and Center of Mass

by Ron Kurtus (updated 30 May 2023)

Take this Mini-Quiz to check your understanding of the lesson material.

1. If you see two objects in space moving in the same direction and parallel to each, how is the CM between them moving?

The CM is stationary, since the objects are moving together

The CM rotates on its axis

It is moving along with them in the same direction

2. If an object is moving toward the stationary CM, how does the other object mirror the motion?

It moves away from the CM at the same speed

It also moves toward the CM but in the opposite direction

It depends on how fast the CM is moving

3. Why would you view the motion of one object with respect to the other?

It may be a more convenient perspective

You would never view one object with respect to the other

You always do this when on the Earth

If you got all three correct, you are on your way to becoming a Champion in Physics. If you had problems, you had better look over the material again.

Be strong

Resources and references

Ron Kurtus' Credentials


Center of Mass Calculator - Univ. of Tennessee - Knoxville (Java applet)

Center of Mass - Wikipedia

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Mini-Quiz: Relative Motion and Center of Mass

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