CBSE Class 12 · 2023 · ElectrostaticsMultiple Choice

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Assertion (A): Work done in moving a charge around a closed path in an electric field is always zero. Reason (R): Electrostatic force is a conservative force.

(A)Both A and R are true and R is the correct explanation of A.✓ Correct
(B)Both A and R are true but R is NOT the correct explanation of A.
(C)A is true but R is false.
(D)A is false and R is also false.

Answer: (A)

Solution

The electrostatic force is conservative, so the work it does depends only on the end points, not on the path. Around a closed path the start and end points coincide, so the net work is zero:

\oint F \cdot d ℓ = 0

. Thus both the assertion and the reason are true, and the reason correctly explains the assertion.

CBSE Class 12 Board · 2023 · Single correct option

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