Electromagnetic waves are received and then vibrate a speaker which produces sound waves.
Explanation:
The telephone has a receiver-transducer component that can receive electromagnetic wave - radio waves spectrum- and transform them into electric energy. This electric energy is then transformed into sound energy by a speaker. This is how we're able to listen to a phone call.
The opposite happens when we speak on the phone. The sound energy is transformed into electric energy by a microphone – the reverse of a speaker. The transducer now changes the electric energy into electromagnetic waves that travel through space to the recipient in the phone conversation.
