Electrical energy is converted to heat at the rate of___________________?
Correct answer: B. I2R
- A. IRt
- B. I2R
- C. I2Rt
- D. VIt
Explanation
The rate at which electrical energy is converted into heat is electrical power, P = I²R, measured in watts (W). Option c, I²Rt, is the likely mistake because it gives energy in joules (J), not energy per unit time.
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About Power
Power is the rate at which work is done or energy is transferred, with average power calculated over a time interval and instantaneous power found from P = Fv when force and velocity are aligned. Work includes units, mechanical efficiency, and the distinction between power and total work or energy.
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