The velocity with which the water approaches a notch is called

Explanation

Explanation:- The velocity of approaches is defined as the velocity with which the water approaches or reaches the weir or notch before it flows over it. The whirl velocity is the tangential component of absolute velocity at the blade inlet and outlet. This component of velocity is responsible for the whirling or rotating of the turbine rotor. Shear velocity also called friction velocity. It is useful as a method in fluid mechanics to compare true velocities.