A 60 W light bulb operates for 5 minutes. How much energy is consumed?
Correct answer: B. 18000 J
- A. 300 J
- B. 18000 J
- C. 3600 J
- D. 7200 J
Explanation
Energy = Power × Time = 60 × (5 × 60) = 60 × 300 = 18000 J.
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About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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