COMEDK · Physics · 6. Work Power Energy
When water falls from a height of \(80 \mathrm{~m}\) at the rate of \(20 \mathrm{~kg} \mathrm{~s}^{-1}\) to operate a turbine the losses due to frictional force are \(20 \%\) of input energy. How much power is generated by the turbine?
- A 25.6 KW
- B 12.8 KW
- C 62.5 KW
- D 21.6 KW
Answer & Solution
Correct Answer
(B) 12.8 KW
Step-by-step Solution
Detailed explanation
The potential energy of the water falling per unit time is the input power, given by \(P_{in} = \dfrac{mgh}{t} = \left(\dfrac{m}{t}\right)gh\). Given \(\dfrac{m}{t} = 20 \text{ kg s}^{-1}\), \(g = 10 \text{ m s}^{-2}\), and \(h = 80 \text{ m}\), we have…
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