We know in order to switch on a TV we have to connect the TV with electrical system of our house. So, we can say a TV uses electrical energy to run. Now, from TV we get sound and we also see pictures.
Thus TV produces sound energy. And picture is created in TV by lights of varing intensity and colour. So, TV produces light energy. Also, if we place our hand on the backside of a running TV we feel that it is a bit warm. So, a TV also produces some thermal energy.
Overall, we see TV takes electrical energy as input and produces. light energy, sound energy and heat energy. Therefore, in a TV the electrical energy change into light, sound and heat energy.