Question

Give one example in each case 

(a) when heat energy changes into kinetic energy. 

(b) when kinetic energy changes into heat energy. 

(c) when sound energy changes into electric energy. 

(d) when electric energy changes into sound energy. 

(e) when light energy changes into chemical energy. 

(f) when chemical energy changes into light energy. 

(g) when electric changes into magnetic energy. 

(h) when magnetic energy changes into electric energy. 

(i) when potential energy changes into electric energy. 

(j) when electric energy changes into potential energy.

Answer 1

(a) In steam engine heat energy moves the wheels of engine and changes into kinetic energy. 

(b) When we rub the palms of our hands fast they become warm hence K.E changes into heat energy. 

(c) Sound energy of microphone changes into electrical energy. 

(d) Electrical energy changes into sound energy while flowing through the speaker. 

(e) Exposure of photographic film in Sun light. 

Or 

During photosynthesis light energy changes into chemical energy. 

(f) Burning of match stick by friction. 

(g) The electrical energy in an electromagnet changes into magnetic energy. 

(h) Motion of magnet in the coil i.e. in generaters. 

(i) When water stored in dam rotates the turbine to produce electricity. 

(j) During the pumping of water in an overhead tank by an electric motor pump, the electrical energy changes into kinetic energy of water. The kinetic energy of water then changes into potential energy.