Photovoltaic cells use _______ to produce electricity.
Coal is a widely used energy resource. Which of the following energies is stored in coal?
The energy change that take place in a photovoltaic cell is
State the energy changes in the following cases while in use:
(a) loudspeaker
(b) a steam engine
(c) microphone
(d) washing machine
(e) a glowing electric bulb
(f) burning coal
(g) a solar cell
(h) bio-gas burner
(i) an electric cell in a circuit
(j) a petrol engine of a running car
(k) an electric toaster
(l) a photovoltaic cell
(m) an electromagnet.