Question

Water falls from a height of $60m$ at the rate of $15kg/s$ to operate a turbine. The losses due to frictional force are $10\%$ of the input energy. How much power is generated by the turbine? $\left(g=10m/s^2\right)$

• A. 10.2 kW
• B. 8.1 kW
• C. 12.3 kW
• D. 7.0 kW

Answer 1

Answer: (B)

$<br/>h=60m<br/>$
$<br/>\begin{array}{l}<br/>\frac{m}{t}=15kg/s\\ <br/>g=10m/s^2<br/>\end{array}<br/>$
Loss due to friction force is $10\%$, only $90\%$ input is used to generate power,
$<br/>P=gh\frac{m}{t}\times \frac{90}{100}<br/>$
$<br/>P=10\times 60\times 15\times 0.9<br/>$
$<br/>P=8.1kW<br/>$