Question

what is the focus of the earthquake

Answer 1

The focus of an earthquake is also known as Hypocentre of Earthquake.
This is the place where the earthquake begins.
The vibrating waves travel away from the focus in all directions.
The waves can be powerful they will reach all parts of the earth and cause it to vibrate like a tuning fork..

Hope this may helps uu..................

Answer 2

Answer :

$\implies$ Scientists (Geologists) call the point of origin of the earthquake,i.e. the point at which tension is released,as its Focus. Since this is often deep below the surface of earth,and difficult to map,it's location is specified by the point(place) on the surface of the earth,directly above the focus. This point, on the surface of earth, is known as Epicentre of the earthquake. The shock/seismic waves move outwards from the epicentre. The maximum damage ,due to an earthquake,usually occurs closest to its epicentre. The strength/intensity of the earthquake decreases away from the epicentre. The whole phenomenon may last for just a few seconds.