Question

Assertion: Power developed in circular motion is always zero.

Reason: Work done in case of circular motion is zero.

• A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
• B. If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
• C. If Assertion is true but Reason is false.
• D. If the Assertion and Reason both are false.
• E. If Assertion is false but Reason is true.

Answer 1

The correct option is A

If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.

Explanation for Assertion statement:

An object undergoing uniform circular motion have acceleration but no displacement.

Power is rate of doing work. It is given by

$P=\frac{W}{t}$

Where,

$P=$ power

$W=$ work done

$t=$ time

Since, displacement is zero, work done become zero. And power will also be zero.

The work done by the conservation force for a closed path is zero.

Therefore, Power developed in circular motion is always zero.

Explanation for Reason statement:

Work done depends on the displacement of a body. In a circular motion, there is no displacement. Therefore, the work done is zero.

Since, Power developed in circular motion is always zero because the work done by the conservation force for a closed path is zero.

Therefore, both assertion and reason are true and the reason is the correct explanation of the assertion.

Hence, option A is correct.