Assume 'A' does 500 J of work in 'x' minutes and 'B' does 1000 J of work in 20 minutes. If the power delivered by 'A' is P_1 and 'B' is P_2 and P_1=2P_2 then 'x', in minutes is :
- A. 10
- B. 5 ✓
- C. 20
- D. 25
Correct Answer: B. 5
Explanation
Power is Work/Time. For B, P_2 = 1000 / 20 = 50 J/min. Given P_1 = 2P_2, we get P_1 = 100 J/min. For A, P_1 = 500 / x = 100, yielding x = 5 minutes.
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