Question

Q1)“energy stored in a spring of watch” Comment on it

Q2)why does a saw becomes warm it is used to cut a log of wood? State energy transformation:

Answer 1

(1) The energy stored in a spring of a watch is potential energy which is as a result of winding of the string. This energy is used to run the watch as it converts this potential energy to rotational kinetic energy.

(2) The saw becomes warm on account of friction as it rubs against the wood. Friction causes heat. The energy conversion in this case is from mechanical (muscular) energy to heat energy.