NEETPhysicsWork Energy and PowerMCQ+4 / −1
Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional forces are 10% of energy. How much power is generated by the turbine ? (g = 10 m/s2)
- A12.3 kW
- B7.0 kW
- C8.1 kW
- D10.2 kW
View written solutionFree
Correct answer: C
It is seen that input power to turbine will be
the potential energy due to water falling in a second
which is equal to
mgh = 15×10×60
= 9000 watt
Now power generated by turbine is 10% less than
above value equal to
(9000 – 900) watt = 8100 watt
= 8.1 kW
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