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Standard XII

Physics

Average and Instaneous Power

A hydroelectr...

Question

A hydroelectric power station take sits water from a lake whose water level is at a height of 50 m above the turbine. Assuming an overall efficiency of 40%, calculate the mass of water which must flow through the turbine each second to produce a power output of 1 MW.(Take g=10 m $s^{- 2}$ ).

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Solution

Since effieciency is 40 %

Useful energy = 40% mgh

$= \frac{40}{100} \times m \times 10 \times 50$

1MW = 200m

1000000 = 200m

m = $\frac{1000000}{200}$ = 5000kg

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Average and Instaneous Power

Standard XII Physics

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A hydroelectric power station take sits water from a lake whose water level is at a height of 50 m above the turbine. Assuming an overall efficiency of 40%, calculate the mass of water which must flow through the turbine each second to produce a power output of 1 MW.(Take g=10 ms−2).

Since effieciency is 40 % Useful energy = 40% mgh =40100×m×10×50 1MW = 200m 1000000 = 200m m = 1000000200= 5000kg

A hydroelectric power station take sits water from a lake whose water level is at a height of 50 m above the turbine. Assuming an overall efficiency of 40%, calculate the mass of water which must flow through the turbine each second to produce a power output of 1 MW.(Take g=10 m $s^{- 2}$ ).

Since effieciency is 40 %

Useful energy = 40% mgh

$= \frac{40}{100} \times m \times 10 \times 50$

1MW = 200m

1000000 = 200m

m = $\frac{1000000}{200}$ = 5000kg