$A$ water sprinkler used for grass lawns begins to rotate as soon as the water is supplied. Explain the principle on which it works.

(N/A) The rotation of the water sprinkler is based on Newton's $Third$ Law of Motion.
When water is supplied, it rushes out through the nozzles of the sprinkler at a high velocity.
According to Newton's $Third$ Law of Motion, for every action, there is an equal and opposite reaction.
The water exerts an action force on the nozzle in the backward direction, and the nozzle exerts an equal and opposite reaction force on the water.
Due to this reaction force, the sprinkler arm experiences a torque that causes it to rotate in the opposite direction of the water flow.