Motion blur only appear on your sensor when the subject you are shooting moves whilst the shutter is open. Most camera’s have a maximum shutter speed of 1/4000 of a second. Think about how short a duration 1/4000 of a second is. Not very long! Therefore using a shutter speed of 1/4000s will have the effect of making speeding object appear still because they don’t move very far in 1/4000s and therefore don’t cause any blur on the sensor.
Here is an examples:
In this photo a shutter speed of 1/4000s was used. Our subject is flying through the air, but because he moves very little distance in 1/4000 of a second he is frozen by the fast shutter speed and looks still.
It is not only 1/4000s that freezes motion. 1/100s will freeze a slow moving subject such as a person walking.
The easiest way to use a fast shutter speed is to put your camera in Tv or S mode and select a fast shutter speed. The camera will take care of the rest.
Be aware that using a very fast shutter speed in dull conditions will mean you camera cannot open it’s aperture up enough to let in enough light and your photo will be underexposed. Your camera will usually flash a warning when this is the case.