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A : When the velocity of an object is ze...

A : When the velocity of an object is zero at an instant, the acceleration need not be zero at that instant.
R : In motion under gravity, the velocity of body is zero at the top - most point.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).

C

If Assertion is true statement but Reason is false, then mark (3).

D

If both Assertion and Reason are false statement, then mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion (A) and the reason (R) provided in the statement. ### Step-by-Step Solution: 1. **Understanding the Assertion (A)**: - The assertion states that when the velocity of an object is zero at an instant, the acceleration need not be zero at that instant. - This is true because acceleration is defined as the rate of change of velocity. If the velocity is momentarily zero, it does not imply that the object is not accelerating. 2. **Understanding the Reason (R)**: - The reason states that in motion under gravity, the velocity of a body is zero at the top-most point. - This is also true. For example, when a ball is thrown upwards, it reaches a point where its velocity becomes zero before it starts descending. 3. **Connecting A and R**: - The assertion (A) is correct, as explained above. The reason (R) is also correct, as it provides a specific example of motion under gravity where the velocity is zero. - However, we need to evaluate whether the reason correctly explains the assertion. The reason provides an example of a situation where the assertion holds true, but it does not explain the concept behind why acceleration can be non-zero when velocity is zero. 4. **Conclusion**: - Both the assertion (A) and the reason (R) are correct statements, but the reason does not adequately explain the assertion. Therefore, the correct conclusion is that A is correct, and R is correct, but R is not the correct explanation for A. ### Final Answer: - A is correct, and R is correct, but R is not the correct explanation for A.
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Knowledge Check

  • Assertion: If velocity of a particle at a certain instant is zero then its acceleration must also be zero at the same instant. Reason: When a particle is projected upward under gravity then at the top point its instantaneous velocity becomes zero.

    A
    both assertion and reason are correct and reason is a correct explanation of the assertion.
    B
    both assertion and reason are correct but reason is not the correct explanation of assertion.
    C
    assertion is correct but reason is incorrect
    D
    assertion is incorrect but reason is correct.

  • Statement-1: When velocity of a particle is zero then acceleration of particle must be zero at that instant Statement-2: Acceleration is equal to a= v ((dv)/(dx)) , where v is the velocity at that instant .

    A
    Statement-1 is true, Statement-2 is true, Statement-2 is a correct explanation for Statement-1
    B
    Statement-1 is true, Statement-2 is true, Statement-2 is not a correct explanation for Statement-1.
    C
    Statement-1 is true, Statement-2 is false
    D
    Statement-1 is false, Statement-2 is true

  • Statement-I : When velocity of a particle is zero then acceleration of particle is zero. Statement-II : Acceleration is equal to rate of change of velocity.

    A
    Statement-I is true, Statement-II is true, Statement-II is correct explanation for Statement-I
    B
    Statement-I is true, Statement-II is true, Statement-II is NOT a correct explanation for Statement-I
    C
    Statement-I is true, Statement-II is false
    D
    Statement-I is false, Statement-II is true.

    • Similar Questions

    Explore conceptually related problems

    If the instantaneous velocity of a particle is zero, will its instantaneous acceleration be necessarily zero?

    If the instantaneous velocity of a particle is zero, will its instantaneous acceleration be necessarily zero

    Give examples where a. the velocity of a particle is zero buts its acceleration is not zero. b.the velocity is opposite in direction to the acceleration, c. the velocity is perpendicular to the acceleration.

    Assertion : An object may have varying speed without having varying velocity. Reason : If the velocity is zero at an instant, the acceleration may not be zero at that instant.

    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.

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