Assertion: If a body is momentarily at rest, it means that force or acceleration are necessarily zero at that instant. Reason: Force on a body at a given time is determined by the direction of motin only.A. If both assertion and reason are ture and reason is the correct explanation of assertion.B. If both assertion and reason are ture but reason is not the correct explanation of assertion.C. If assertion is ture but reason is false.D. If both assertion and reason are false.

Assertion: If a body is momentarily at rest, it means that force or ac

1.	Assertion: If a body is momentarily at rest, it means that force or acceleration are necessarily zero at that instant. Reason: Force on a body at a given time is determined by the direction of motin only.A. If both assertion and reason are ture and reason is the correct explanation of assertion.B. If both assertion and reason are ture but reason is not the correct explanation of assertion.C. If assertion is ture but reason is false.D. If both assertion and reason are false.
Answer» Correct Answer - D If a body is momentarily at rest i.e., `v=0` at an instant, it does not mean that force or acceleration are necesserily zero at that instant. For example, when a ball thrown upward reaches its maximum height, `v=0 ` but the force continue to be its weight `mg` and the acceleration is `g` . Force is not always inn the direction of motion.

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