Question

Statement I:If a body is momentarily at rest, it means that force or acceleration are necessarily zero at that instant
Statement II:Force on a body at a given time is determined by the direction of motion only

• A. If both Statement I and Statement II are true and the Statement II is correct explanation of the Statement I
• B. If both Statement I and Statement II are true but the Statement II is not the correct explanation of the Statement II
• C. If Statement I is true but Statement II is false
• D. If both the Statements are false

Answer 1

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 necessarily zero at that instant. For example, when a ball thrown upward reaches its maximum height, $v=0$ but the force continues to be its weight $mg$ and the acceleration is $g$. Force is not always in the direction of motion