(a)[1]
State the principle that energy is conserved.
(b)[3]
Fill in the sentences about energy changes in the stop-watch that measures a time interval. (i) The type of energy stored in the battery is [BLANK] energy. (ii) The type of energy stored in the stop-watch’s second hand is [BLANK] energy. (iii) The stop-watch has a bell. When the bell rings, energy is transferred to the surroundings as [BLANK] energy.