Calculate the work done in a resistor of 20 ohms carrying 5A of current in 3 hours.
Correct answer: B. 1.5 kWh
- A. 1 kWh
- B. 1.5 kWh
- C. 2 kWh
- D. 3 kWh
Explanation
Work done is equal to energy which is power divided by timeE=P x tP =I2 x R = 52 x 20 = 500 WE = 500 x 3 = 1500 J1500 J = 1.5kWh
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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