DC circuitsQuestion 567 of 1506

A source has 120 V across its terminals in an open circuit. What power is dissipated?

120 W
14 400 W
1.2 W
0 W

Show answer

Correct answer: 0 W

There is no current, so P = I x E = 0.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 2.3: Power in Electric Circuits

Questions last reviewed: 18 October 2026

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