Work Energy And Power Ques 38
38. Water falls from a height of $60$ $ m$ at the rate of $15$ $ kg / s$ to operate a turbine. The losses due to frictional force are $10 \%$ of energy. How much power is generated by the turbine? ( $g=10$ $ m / s^{2}$ )
[2008]
(a) $8.1 $ $kW$
(b) $10.2 $ $kW$
(c) $12.3 $ $kW$
(d) $7.0 $ $kW$
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Answer:
Correct Answer: 38.(a)
Solution:
- (a) Given, $h=60 $ $m, g=10$ $ ms^{-2}$,
Rate of flow of water $=15 $ $kg / s$
$\therefore$ Power of the falling water
$=15 $ $kgs^{-1} \times 10$ $ ms^{-2} \times 60$ $ m=9000$ watt
Loss in energy due to friction
$=9000 \times \frac{10}{100}=900$ watt.
$\therefore$ Power generated by the turbine
$=(9000-900)$ watt $=8100$ watt $=8.1$ $ kW$
BETA
