The height of the dam is 20 m at a hydroelectric power plant. How many of kg of water must fall per second on the blades of a turbine to generate one mega watt of electrical power? (g=10 m/s2)
Correct answer: D. 5000 kg/s
- A. 1000 kg/s
- B. 2000 kg/s
- C. 4000 kg/s
- D. 5000 kg/s
Explanation
The formula of power isPower = W/t = PE/t = mgh/tm/t = P/gh = 10⁶/(10)(20) = 5000 kg/sHence, this option is correct.
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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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