Waves As Carrier Of Energy

Q.8.  Explain waves as carrier of energy and write the two methods of transfer of energy.

Ans: 
      Energy can be transfer from are point to another by two methods

                  i  Through Matter                                    ii   Through waves

Trough Matter:

In the First Case we can take example of a bullet which is fired from a gun. It has kinetic energy which is carried by the bullet and is transferred this energy to the target when it hits the target. Similarly the fast moving water coming out for the tunnel of a dam has K.E which is transferred to the turbine when water strikes its blades.
The other method of transfer of energy is by the help of waves without transfer of mass.

Through Waves.

Energy can be transferred from one place to another place through waves, For example energy is transferred from the sun to Earth by means of waves.

Experiment:

when a stone is dropped into a pond of water, then energy is transferred from stone to the water and as a result waves are produced in the water.
These waves spread over surface of water and molecules of water start oscillating.

If apiece of cork is already placed in water we can easily observe the oscillating motion of the cork. The propagation of waves over surface of water carries energy which is being transferred to molecules of water. It is an example of transfer of energy without transfer of mass.