Speed of Earth

There are many ways we can tell the speed of the Earth. We can tell how long it takes to rotate in its own axis, the speed it travels around the Earth and we can also tell the time the Earth takes to revolve around the sun. 

Spinning in its own axis (rotation)

Rotation is the spinning of the Earth on its own axis (its not only the Earth but is written so to make you understand). When the Earth completes a rotation, we call it as a day. To complete a rotation, the Earth takes 23 hours, 56 minutes and 4.1 seconds. (That is why a leap year comes).

Going around the sun (revolution)

Revolution is the Earth going around the sun (this too is not only for the Earth but is written so just to make you understand). When the Earth completes a revolution, we call it as a year. The Earth takes 365.26363 days to complete a revolution.

Speed of Earth when going around the sun

When going around the sun, the Earth travels at a speed of  30km per second. That is 1800km per hour.