See Our New JEE Book on Amazon
Question: The video shows a plastic bottle hanging by threads. Water comes out of the holes made in the four walls and the bottle rotates in an anticlockwise direction as seen from the top. Consider the plastic bottle (not water in it) as the system. The anticlockwise torque to rotate it comes from
Solution: The water flowing out of the bottle carries a momentum.The water flowing out of the four holes applies force on the bottle. The torque due to these forces about the centre of mass of the bottle rotate it in the anticlockwise direction (as seen from the top).
Thus, option (B) is correct.
Also See This Related Experiment
See Our Books