Question

State energy changes which occur in the following devices:

i) microphone
ii) loudspeakers
iii) bicycle dynamo
iv) hydroelectric power Dam

Answer 1

Energy changes in different devices include converting sound energy into electrical energy in microphones, converting electrical energy into sound energy in loudspeakers, converting mechanical energy into electrical energy in bicycle dynamos, and converting the potential energy of flowing water into electrical energy in hydroelectric power dams.

Step-by-step explanation:

In a microphone, energy changes occur when sound waves cause the diaphragm to vibrate, converting sound energy into electrical energy.

In loudspeakers, electrical energy is converted into sound energy when an electric current passes through a coil, creating a magnetic field that interacts with a permanent magnet, causing the cone or diaphragm to vibrate and produce sound.

In a bicycle dynamo, mechanical energy is converted into electrical energy when the wheel spins a generator, producing an electric current.

In a hydroelectric power dam, the potential energy of flowing water is converted into electrical energy as the water flows through turbines, causing them to rotate and generate electricity.