If a machine does 50 J of work in 10 s, then the power of the machine will be
Correct answer: A. 5 W
- A. 5 W
- B. 40 W
- C. 60 W
- D. 500 W
Explanation
The power of a machine is calculated using the formula: Power = Work / Time. In this instance, the work done is 50 joules and the time taken is 10 seconds. Therefore, Power = 50 J / 10 s = 5 watts. Option A is correct. The other options (40 W, 60 W, and 500 W) do not match the result from the formula and are incorrect.
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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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