Distinguish between streamline and turbulent motion:

If a liquid flows in such a way that its velocity at any point is always the same in magnitude as well as in the direction, then the flow of the liquid is said to be steady or streamline flow.

On the other hand, if a liquid flows in such a way that the velocity at a given point varies with time both in magnitude and direction in an irregular manner, the flow of the liquid is said to be turbulent.

When the velocity of the liquid exceeds the critical velocity then the streamline flow becomes turbulent. The nature of the flow of the liquid is determined by Reynold’s number. If the value of Reynold’s number varies from 0 to 2000, then the motion is streamline flow. If the value of Reynold’s number is greater than 3000 then the motion is turbulent motion. When the value of Reynold’s number lies between 2000 to 3000, then we can conclusively predict its nature, i.e, transition region in which the motion may change at any time from streamline to turbulent motion.