The consumption of energy by 60-watt bulb in 2 seconds is:
Correct answer: B. 120 J
- A. 20 J
- B. 120 J
- C. 30 J
- D. 0.02 J
Explanation
The energy consumed by a 60-watt bulb in 2 seconds can be calculated using the power formula: P = E/t. Here, P is the power in watts (60 W), E is the energy in joules, and t is the time in seconds (2 s). Rearranging the formula gives E = P × t, which results in E = 60 × 2 = 120 J. Option B is correct. The other options provide incorrect values due to miscalculation or misunderstanding of the formula.
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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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