Which of the following objects is in equilibrium?
(A) A rocket rising at a constant rate.
(B) A thrown stone at its highest point.
(C) Any object in free fall.
(D) A baseball being thrown.
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What this question is about
Which of the following objects is in equilibrium?
(A) A rocket rising at a constant rate.
Yes. It is not accelerating.
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Which of the following objects is in equilibrium?
(B) A thrown stone at its highest point.
No. It's velocity is zero
but its acceleration is not.
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Which of the following objects is in equilibrium?
(C) Any object in free fall. --- No.
Such an object is accelerating downward.
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Which of the following objects is in equilibrium?
(D) A baseball being thrown. --- No.
It is being acted on by an unbalanced force.
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