Momentum Multiple Choice Question

AI Thread Summary
In the discussion about a boy stepping off a skateboard, the incorrect statement regarding momentum is identified as D, since momentum is not energy but a measurement of motion. The conversation highlights that when the boy lands, he exerts an impulse on the ground, and the ground exerts an equal impulse back on him, illustrating Newton's Third Law. Additionally, it is confirmed that the ground can exert an impulse on other objects, such as bouncing balls. This exchange of impulses is fundamental to understanding momentum and motion dynamics. Overall, the key focus is on the principles of momentum and impulse in physical interactions.
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A boy traveling on a skateboard steps off the board perpendicular to its motion. After stepping off, the boy lands on the ground and comes to rest. Which one of the following statements is INCORRECT?

A The boy exerts an impulse on the ground on impact
B The ground exerts an impulse on the boy on impact
C The momentum possessed by the boy before the collision is shared with the earth
D The momentum possessed by the boy before the collision is transformed to heat



Would the answer be D because momentum is not a form of energy; rather, it is a measurement which shows the tendency of an object to move in its line of direction.

Furthermore, can the ground exert an impulse on objects such as bouncing balls, etc?
 
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Procrastinate said:
A The boy exerts an impulse on the ground on impact
B The ground exerts an impulse on the boy on impact
C The momentum possessed by the boy before the collision is shared with the earth
D The momentum possessed by the boy before the collision is transformed to heat

Would the answer be D because momentum is not a form of energy; rather, it is a measurement which shows the tendency of an object to move in its line of direction.
That is correct.
Furthermore, can the ground exert an impulse on objects such as bouncing balls, etc?
Yes. A bouncing ball exerts an impulse on the Earth and the Earth exerts an equal in magnitude but opposite in direction impulse on the ball. This is a consequence of Newton's Third Law.
 
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