Question

Rank the boxes on the basis of the magnitude of the normal force acting on them. Rank from largest to smallest.

a. 140 N pushing on 5 kg box against wall
b. 140 N pushing on 3 kg box against wall
c. 120 N pushing on 3 kg box against wall
d. 150 N pushing on 7 kg box against wall
e. 130 N pushing on 7 kg box against wall
f. 150 N pushing on 1 kg box against wall

Answer 1

Answer:

The ranking of the normal force acting on the boxes from largest to smallest is;

150N (7kg) = 150N(1kg) > 140N(5 kg) = 140N(3kg) > 130N(7kg) > 120N(3kg)

Explanation:

To rank these boxes on the basis of the normal force acting on them, we will apply Newton's second law of motion. Since, the boxes are  stationary, the horizontal forces acting on each of them will sum up to zero, thus giving the value of normal force acting on each box.

Let the force acting on each box = F

Let the normal force acting each box = N

The net horizontal force on the boxes = 0

∑Fx = 0

F - N = 0

F = N

Since the normal force acting on each box is equal to force acting on each box, the ranking  from largest to smallest is as follows;

150N (7kg) = 150N(1kg) > 140N(5 kg) = 140N(3kg) > 130N(7kg) > 120N(3kg)