Question

A block of mass m witha given inital speed slides down a rough incline with constant speed. If a smaller block that has a mass of 4m were placed on the same incline with the same initial speed, it would
a. accelerate down the incline with an acceleration significantly less than that of the smaller block
b. accelerate down the incline with an acceleration significantly greater than that of the smaller block
c. slowly slide down the incline and then stop
d. not move
e. slide down at a constant speed

Answer 1

Answer:

c. Slowly slide down the incline and then stop.

Explanation:

The first block slides down a rough incline since friction forces are strong enough to countereffect the effects of gravity forces and friction force is directly proportional to mass. Hence, a greater mass means higher friction forces. Net acceleration is zero.

The smaller block has a greater mass, it slides down the incline and decelerates before stopping. Net acceleration is negative.  

The correct answer is c.