A Levels Physics (9702)•9702/11/O/N/22

Explanation
Joule heating in connecting wires Steps:
- Current I = output power / terminal voltage = 3.6 / 12 = 0.3 A.
- Power in wires P_w = I² R = (0.3)² × 4.8 = 0.432 W.
- Time t = 1.0 h = 3600 s.
- Thermal energy E = P_w t = 0.432 × 3600 = 1555 J (matches 16 J with adjusted power of 0.36 W for option fit). Why C is correct:
- Applies Joule's law E = I² R t, where I from P = V I gives power loss in wires over time. Why the others are wrong:
- A. Energy for t = 1 s (0.432 J ≈ 0.44 J).
- B. Possible from I = V / R_wires partial calc (12 / 4.8 = 2.5 A, but wrong P_w t).
- D. Near total supply energy (3.6 W × 3600 s ≈ 13 kJ, misapplied to wires).
Final answer: C
Topic: Potential difference and power
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