What is the average power required to lift a mass of 100kg to a height of 50m in 50 Seconds?
Correct answer: B. 980 W
- A. 100 W
- B. 980 W
- C. 50 W
- D. 5000 W
Explanation
To calculate the average power required to lift a mass, we can use the formula: Average Power = Work / Time The work done to lift a mass to a certain height is given by the formula: Work = Force x Distance In this case, the force required to lift the mass is equal to its weight, which is calculated as Force = Mass x Acceleration due to gravity Acceleration due to gravity is approximately 9.8 m/s². Now, let's calculate the work done: Work = (Mass x Acceleration due to gravity) x Distance = (100 kg) x (9.8 m/s²) x (50 m) = 49,000 J The average power can be calculated by dividing the work by the time: Average Power = Work / Time = 49,000 J / 50 s = 980 W
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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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