Answer the following in one or two sentences:

What are seismic waves and mention its types?

Seismic waves are generally generated when there is an earthquake on the surface. Earthquake creates seismic waves. The seismic waves are the speed and force of the waves at which it depends on the medium at which it's travel. For seismic waves there are mainly three types of waves:

a. primary or p- waves

b. secondary or s- waves

c. surface waves or L- waves

• Primary waves or P-waves

The primary waves are popularly known as P-waves. P- waves are the fastest waves of all earthquake and it's the to reach the epicentre and it travels through solid, liquid, gases and the average velocity of P- waves are 5.3km per second to 10.6 km per second.

• Secondary waves or S- waves

This travels only through the solids. These waves shake the ground in the perpendicular direction. The average velocity of S- waves is 1km per second to 8km per second.

• Surface waves or L- waves

Are similar to P- waves but they travel through ground surface. Compare to other waves L- waves are very slow and it's most destructive. The average velocity of these waves is 1km per second to 5 km per second.