A block of mass m is pulled along a rough horizontal floor by an applied force as shown. The vertical component of the force exerted on the block by the floor is:
A) mg
B) mg - T cos $\theta$
C) mg + T cos $\theta$
D) mg - T sin$\theta$
E) mg + T sin $\theta$

Question

A block of mass m is pulled along a rough horizontal floor by an applied force as shown. The vertical component of the force exerted on the block by the floor is: 
A) mg 
B) mg - T cos $\theta$ 
C) mg + T cos $\theta$ 
D) mg - T sin$\theta$ 
E) mg + T sin $\theta$

Quizplus · Accepted Answer

The vertical component of the force exerted on the block by the floor is equal in magnitude and opposite in direction to the vertical component of the force exerted by gravity, which is mg. The horizontal component of the tension force is canceled by the applied force. Therefore, the only remaining force that could contribute to the vertical component is the horizontal component of the weight T sin(θ), which acts in a downward direction. Thus, the vertical component of the force exerted on the block is mg - T sin(θ).

A Block of Mass M Is Pulled Along a Rough θ\thetaθ

A Block of Mass M Is Pulled Along a Rough $\theta$