Engineering Board Exam Reviewer · Energy and Power · hard
A resistor dissipates 2 W when connected across a battery. A second identical resistor is connected in parallel with the first. What total power does the battery now supply?
- 1 W
- 2 W
- 8 W
- 4 W
Answer
D. 4 W
Solution
Each resistor still has the full battery voltage across it, so each dissipates 2 W. The total is 2+2=4 W.
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