Answer:
Explanation:
a )
one kg of coal gives energy of 27 x 10⁶ J
75 kg of coal gives energy of 27 x 10⁶ x 75 J
So rate which energy is coming out of coal per second
= 27 x 10⁶ x 75 J
= 2025 x 10⁶ J /s
2025 million watts .
b ) energy output = 800 million watts
efficiency = (800 / 2025) x 100
= 39.5 % .
To solve this problem, we will start by defining each of the variables given and proceed to find the modulus of elasticity of the object. We will calculate the deformation per unit of elastic volume and finally we will calculate the net energy of the system. Let's start defining the variables
Yield Strength of the metal specimen

Yield Strain of the Specimen

Diameter of the test-specimen

Gage length of the Specimen

Modulus of elasticity



Strain energy per unit volume at the elastic limit is



Considering that the net strain energy of the sample is




Therefore the net strain energy of the sample is 
1km per 5 mins
PLEASE VERIFY WITH SOMEONE I MAY BE INCORRECT