How much work must be done by a force on 50 kg body in order to accelerate it from rest to 20 m/s in 10 s?
Correct answer: C. 104J
- A. 2 x 10^3J
- B. 103J
- C. 104J
- D. 4 x 10^4 J
Explanation
Correct.Change in K.E = 1/2 mv²W= 1/2 50×20^2W= 10000J
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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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