The tube shown in figure is of uniform cross-section. Liquid flows through it at a constant speed in the direction shown by arrows. Then the liquid exerts on the tube is:

Options

A. a net force to the right
B. a net force to the left
C. a clockwise torque
D. an anticlockwise torque

Answer

C

Explanation

At bends, liquid undergoes change in momentum only hence the liquid and tube exert forces on each other. The two form a couple exerting a clockwise torque.
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