Question

Gabrielle and Pierre are trying to move a 52 kg box by pushing it across the floor. Gabrielle is pushing with a force of 40 N [east], while Pierre is pushing with a force of 32 N [west]. There is also a friction force of 3 N [west] on the box. Assume the box travels 4 m [east].A. Draw a system diagram and a free-body diagram of the box.B. Calculate the net force in the horizontal direction on the box. In which direction is the net horizontal force?C. Calculate the net force in the vertical direction on the box. In which direction is the net vertical force?

Answer 1

Explanation

Step 1

a)system diagram and Free body diagram

F.B.D.

Step 2

B)

Net force:

Let

positive to the rigth, negative to the left, so

$\begin{gathered} Net\text{ force=40 N-32N-3N=5 N} \\ Net\text{ force=5 N} \end{gathered}$

so, the net force is 5 N (east)

Step 3

net force in the vertical direction:

as the box is not moving on the y-axis, the sum of forces equals zero, hence

$\begin{gathered} N-mg=0 \\ N=weight=mg=52kg*9.8\frac{m}{s^2} \\ Normal\text{ force=509.6 N} \end{gathered}$

so

the net force in the vertical direction is zero

I hope this helps you