Question Details

From a water fall, water is falling at the rate of 100 kg/s on the blades of turbine. If the height of the fall is 100m then the power delivered to the turbine is approximately equal to

Options

A

100 kW

B

10 kW

C

1 kW

D

1000 kW

Correct Answer :

100 kW

Solution :

The correct option is 100 kW.

To find the power delivered to the turbine, we can calculate the rate at which gravitational potential energy is transferred to the turbine blades by the falling water.

First, let us identify the given values from the problem statement:
- Rate of flow of water, which is the mass of water falling per unit time: dmdt=100 kg/s
- Height of the waterfall: h=100 m
- Acceleration due to gravity (g) is approximately 10 m/s2

The potential energy (E) of a mass of water m at a height h is given by:
E=mgh

Power (P) is the rate at which energy is delivered or work is done over time (t). Thus, we differentiate energy with respect to time:
P=dEdt=ddt(mgh)

Since the height h and gravity g remain constant during the fall, we can rewrite the equation as:
P=ghdmdt

Now, substituting the given values:
P=10 m/s2×100 m×100 kg/s
P=100,000 W

To express this power in kilowatts (kW), we divide the value in Watts by 1,000 (since 1 kW = 1,000 W):
P=100,0001,000 kW=100 kW

Therefore, the power delivered to the turbine is approximately equal to 100 kW.

Unlock Our Free Library

Access expert-curated educational resources and study materials—completely free.

Discover more resources

You may also like

Mock Tests

View All
  • JEE
  • intermediate
  • 3 hours
  • chemistry, mathematics, physics

  • JEE
  • intermediate
  • 3 hours
  • chemical engineering, mathematics, physics