How strong is the earthquake?

The magnitude 7.8 earthquake occurred on April 25 in Nepal, causing more than 2,500 people to die and this number continues to increase. So how strong is the earthquake intensity, how strong can it be to cause such deaths and destruction?

Please see the graphic depicting the power of earthquakes that happened in the world and the damage caused by earthquakes.

Below are the earthquake and its destructive power levels

Picture 1 of How strong is the earthquake?
As of April 30, more than 5,000 people were killed by earthquakes in Nepal

Picture 2 of How strong is the earthquake?
This earthquake is equivalent to 15,000 tons of TNT

Picture 3 of How strong is the earthquake?
There are about 4500 earthquakes ranging from 2-2.9 Richter annually

Picture 4 of How strong is the earthquake?
There are about 2000 earthquakes with a magnitude of 5- 5.9 richter per year

Picture 5 of How strong is the earthquake?
Energy of earthquake 6.7 richter equivalent to 338,000 tons of TNT

Picture 6 of How strong is the earthquake?
The earthquake's magnitude of 7 from the richter is similar to the 31.7 nuclear bomb Little Boy

Picture 7 of How strong is the earthquake?
The 7.6-magnitude earthquake at Tangshan, China claimed the lives of 255,000 people

Picture 8 of How strong is the earthquake?
The 8.3-magnitude earthquake has the equivalent of 38.24 million tons of TNT

Picture 9 of How strong is the earthquake?
The 9-magnitude earthquake is equivalent to 15,933 Little Boy nuclear bombs

Picture 10 of How strong is the earthquake?
Picture 11 of How strong is the earthquake?
A seismic of more than 9 magnitudes is called a powerful earthquake

Picture 12 of How strong is the earthquake?
The energy of the 9.5-magnitude earthquake is equivalent to 80% of the solar energy shining on the earth in 60 seconds

Picture 13 of How strong is the earthquake?
No earthquake has ever reached 10 richter scale, but if so, the energy level released is 1 million million tons of TNT