Two bodies P and Q on a smooth horizontal surface are connected by a light cord.The mass of P is greater than that of Q.A horizontal force (of magnitudeF) is applied to Q as shown in the figure, accelerating the bodies to the right. The magnitude of the force exerted by the connecting cord on body P will be

A) zero.
B) less than F but not zero.
C) equal to F.
D) greater than F.

Question

Two bodies P and Q on a smooth horizontal surface are connected by a light cord.The mass of P is greater than that of Q.A horizontal force

(of magnitudeF) is applied to Q as shown in the figure, accelerating the bodies to the right. The magnitude of the force exerted by the connecting cord on body P will be
Two bodies P and Q on a smooth horizontal surface are connected by a light cord.The mass of P is greater than that of Q.A horizontal force (of magnitudeF) is applied to Q as shown in the figure, accelerating the bodies to the right. The magnitude of the force exerted by the connecting cord on body P will be A) zero. B) less than F but not zero. C) equal to F. D) greater than F.

A) zero. 
B) less than F but not zero. 
C) equal to F. 
D) greater than F.

Quizplus · Accepted Answer

Since the cord is light, it can be assumed to be taut at all times.
Therefore, the tension in the cord is equal to the force exerted by body Q on the cord, which is F.
Since the bodies are connected, they will have the same acceleration.
Thus, the net force on body P is (its weight - tension in cord), which is greater than zero.
Therefore, the force exerted by the connecting cord on body P is less than F but not zero.

Two Bodies P and Q on a Smooth Horizontal Surface