Question

An object is represented by the dot on the motion map. Which object is most likely represented by the dot? A. a car driving over the top of a hill B. a ball on a string that stopped at the top of a vertical loop C. a roller coaster car at the top of a vertical loop of a track D. a bug on the top of a rolling hula hoop

Answer 1

B: a ball on a string that stopped at the top of a vertical loop

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Answer 2

Answer:

B. a ball on a string that stopped at the top of a vertical loop

Explanation:

Motion diagram must represent the direction of velocity of an object in the given figure

here as it is shown in the figure the arrow is vertically downwards which means that the velocity of object at that moment is downwards when it is at the top most point of its circular path

So here

A. a car driving over the top of a hill

Not correct as car is moving tangentially on the top of the hill so its velocity can not be downwards

B. a ball on a string that stopped at the top of a vertical loop

Since ball is stopped at the top most point of its path so here its velocity must be downwards due to free fall so its correct motion diagram for the above condition.

C. a roller coaster car at the top of a vertical loop of a track

Not correct as we know that roller coaster at the top of the loop will move tangentially so its velocity can not be vertically downwards.

D. a bug on the top of a rolling hula hoop

Bug is at the top of rolling hula hoop so its velocity is again tangentially and not vertical downwards.