A stream of a liquid of density flowing horizontally with speed v rushes out of a tube of radius r and hits a vertical wall nearly normally. Assuming that the liquid does not rebound from the wall, the force exerted on the wall by the impact of the liquid is given by

Step-by-step solution

Cross-sectional area A= r^2 , Volume of liquid flowing per second =A V= r^2 V Mass of the liquid flowing out per second = r^2 v Initial momentum of liquid per second = mass of liquid flowing Speed of liquid = r^2 v v= r^2 v^2 Since the liquid does not rebound after impact, the momentum after impact is zero. Rate of change of momentum = r^2 v^2 According to Newton's second law, the force exerted on wall = rate of change of momentum = r^2 v^2