Question

Look at the following pictures .Mention the nature of energy transformation that takes place in each.

Answer 1

Hint: Since all devices that convert one form of energy into another works on the principle of law of conservation of energy. Here all given devices will convert one form of energy into another. Like Dry cell is used to give Electricity and fan is used to give air by motion of paddles of fan. Bulbs and solar cells are used to give light.

Complete answer:
Energy is defined as the capacity to do work. There are various forms of energy that exist in nature like Thermal Energy, Chemical Energy, Electrical Energy, Nuclear Energy, Magnetic Energy, Solar Energy, Wind Energy ,Tidal Energy ,Biomass Energy, Wave Energy.

(i) First Figure is of Dry Cell: - Dry cell is a device that converts Chemical Energy into Electrical Energy.
Dry cell or a normal cell has two electrodes one is called anode and one is called cathode which supplies Electrical energy from the chemicals present in the cell.
(ii) Second Figure of Fan: -Fan is a device that converts Electrical Energy into Mechanical Energy.
Fan is a device in which blades of a fan move with some kinetic energy and this kinetic energy comes from electrical energy and this kinetic energy comes from mechanical energy. So Fan is used to convert Electrical energy into Mechanical or Kinetic Energy.
(iii) Third Figure is Bulb: - Bulb is a device that converts Electrical Energy into Light Energy.
When electricity is passed in Bulb then tungsten in the bulb gets heated due to its high resistance and the bulb starts glowing and produces some light which is called light energy or electrical energy.
(iv) Fourth Figure is Solar cell: It is a device that converts Solar energy into Electrical Energy.
Solar energy is taken from the Sun which is the primary source of solar energy. Solar energy is used for various purposes like in making food for plants and also in Solar devices so that we can convert it into some useful forms of energy.

Note: According to the law of conservation of energy, energy can neither be created nor can be destroyed; it can only be converted into one form to the another form. Total energy of the isolated (individual) system remains constant. Universe as a whole is acting as an isolated system, so this law of conservation of energy is valid in the whole universe.