All kinds of laws govern our everyday life. Traffic laws tell that you have to stop at stop signs. Government laws demand that you have to pay income tax on your salary/income, etc. Even scientific laws apply to everyday life. For example, law of gravity forces us to move on earth and we cannot move in the air. Another set of scientific laws that affect our everyday life are the laws of thermodynamics. For example, first law of thermodynamics states that energy can neither be created nor be destroyed but it can be converted from one form to another. This is also sometimes referred to as law of conservation of energy.
Now answer the following questions.
(i) How is first law of thermodynamics applicable to an electrical fan or a heater?
(ii) How does first law of thermodynamics apply to a hydroelectric power plant?
(iii) If a stone at a height falls, it hits the objects or breaks our head. How does first law of thermodynamics apply here?