Engineering Board Exam Reviewer · Energy and Power · medium
The source in the circuit shown is 12 V and the resistor is 4, . How much energy does the resistor use in 2 hours?
- 36 Wh
- 4320 Wh
- 72 Wh
- 0.036 Wh
Answer
C. 72 Wh
Solution
I=V/R=3 A and P=VI=36 W. Energy =Pt=(36 W)(2 h)=72 Wh.
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