Q No. 4:
Compare and contrast fossil fuels and the Sun as direct
sources of energy.
Ans:
Coal and petroleum are fossil fuels they are obtained
from deep under Earth’s crust. They are directly available to human beings for
use. Therefore fossil fuels are the direct source of energy. But these are
limited in amount also they are non-renewable.
Solar energy is also a direct source of energy. But it is renewable source of energy. The Sun
has been shining for several years and will continue billions of years more.
Solar energy is available free of cost to all in unlimited amount.
