Question

A coal power plant station generates electricity at night when it is not needed. Some of this energy is stored by pumping water up to a mountain lake. When there is high demand for electricity, the water is allowed to flow back through a turbine to generate electricity.
1- Write down the forms of initial and final energy transfer.

2- On one occasion, 2000 kg of water is pumped up through a vertical height of 500 m. Calculate the gravitational potential energy. (g= 10 m/s^2)

Answer 1

Answer:

1.) Check the explanation for the answer

2.) 10 MJ

Explanation:

Given that a coal power plant station generates electricity at night when it is not needed. Some of this energy is stored by pumping water up to a mountain lake. When there is high demand for electricity, the water is allowed to flow back through a turbine to generate electricity.1- Write down the forms of initial and final energy transfer.

Solution.

The initial conversion will be :

Chemical energy is converted to mechanical energy.

The final conversion will be :

Mechanical energy is converted to electrical energy. While the electrical energy is converted to light energy.

2- On one occasion, 2000 kg of water is pumped up through a vertical height of 500 m. Calculate the gravitational potential energy. (g= 10 m/s^2)

The gravitational potential energy can be calculated by using the formula

Energy = mgh.

Where

M = mass

H = height

g = acceleration due to gravity

Substitute all the parameters into the formula

Potential Energy = 2000 × 500 × 10

Potential energy = 10000000 Joule

Potential energy = 10 MJ