On moving a charge of 2C from a point A where potential is +12V to a point B where potential is -12V, the work done is:
Correct answer: D. -48 J
- A. +24 J
- B. -24 J
- C. 48 J
- D. -48 J
Explanation
The work done in moving a charge in an electric field is given by the formula W = q (Vf - Vi), where q is the charge and Vf and Vi are the final and initial potentials, respectively.Here, q = 2C, Vi = +12V, and Vf = -12V. The potential difference (Vf - Vi) is -12V - (+12V) = -24V.Therefore, W = 2C × (-24V) = -48 J.The negative sign indicates that work is done by the electric field during the movement of the charge. Options A, B, and C do not correctly apply the formula or consider the sign of the potential difference.
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