Two points P and Q are maintained at the potentials of 10V and -4V respectively. The work done in moving 100 electrons from P to Q is:
Correct answer: D. 2.24 x 10^-16 J
- A. - 9.60 x 10^-17 J
- B. 9.60 x 10^-17 J
- C. - 2.24 x 10^-16 J
- D. 2.24 x 10^-16 J
Explanation
The work done in moving a charge is calculated using the formula: W = q (ΔV), where q is the charge and ΔV is the potential difference.Given the potentials of 10V and -4V, the potential difference (ΔV) is (-4V - 10V) = -14V.The charge of 100 electrons is q = -100 × 1.6 × 10-19 C, since the charge of one electron is -1.6 × 10-19 C.Therefore, W = (-100 × 1.6 × 10-19 C) × (-14V) = 2.24 × 10-16 J.This confirms that Option D is correct, while the other options contain errors in sign or calculation.
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