Explanation:
1) when skating because of friction , some of the kinetic energy is converted to thermal energy.
therefore Kinetic energy is reducing and thermal energy is increasing
2) when the brake pads are applied , the speed get decreased . this will cause the Kinetic energy to reduce. thermal energy is increased due to the friction occur when braking
3) when the boy stop , he no longer has a movement. now the whole amount of kinetic energy should be transfered to another form of energy. So the thermal arises
4) as we know energy can never be destroyed. it can only be transferred in to another form. here the kinetic and the thermal energy were the only types of energy that we could see.
therefore
Total Energy = kinetic energy + thermal energy
