A brick is resting on a rough incline as shown in the figure.The friction force acting on the brick,along the incline,is
A)zero.
B)equal to the weight of the brick.
C)greater than the weight of the brick.
D)less than the weight of the brick.

Question

A brick is resting on a rough incline as shown in the figure.The friction force acting on the brick,along the incline,is 
A)zero. 
B)equal to the weight of the brick. 
C)greater than the weight of the brick. 
D)less than the weight of the brick.

Quizplus · Accepted Answer

Since the brick is resting on the incline, its weight will act downwards perpendicular to the incline while the friction force will act upwards parallel to the incline. The friction force will oppose the motion of the brick and prevent it from sliding down the incline. Therefore, the magnitude of the friction force will be less than the weight of the brick. Therefore, the correct choice is D, less than the weight of the brick.

A Brick Is Resting on a Rough Incline as Shown