Advertisements
Advertisements
Question
A hydroelectric power station takes its water from a lake whose water level is 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 power output of 1 MW. (Take g = 10 m s−2).
Advertisements
Solution
Height h = 50 m, g = 10 ms−2
Power out put = 1 MW = 106 J/S
But this is only 40 %
∴ P.E. required = `100/40 xx 1000000`
= m × 10 × 50
= 2500000
Mass of water = m = `2500000/500`
= 5000 kg
APPEARS IN
RELATED QUESTIONS
A ball is made to fall freely from a height. State the kind/ kinds of energy possessed by the ball when it is at the highest point .
State the changes in form of energy while producing hydro electricity.
Select the renewable and non-renewable sources of energy from the following:
Coal
State two disadvantages of using nuclear energy for producing electricity.
State the energy transformation on the following:
Electricity is obtained from nuclear energy.
Give three examples of bodies possessing potential energy.
State two advantages and disadvantages of using nuclear energy for producing electricity.
Give one example when:
Light energy changes to chemical energy.
You might have seen some beautiful fireworks during Diwali. It is an example of the transformation of ______ energy into ______ energy.
The solar cooker is an application of the ______ energy of the sun, while solar cells, solar lamps are applications of the ______ energy of the sun.
