Question

Brandon is pulling a desk to the right with a force of 26.00 N. The force of friction to the left is 3.00 N.
a. Calculate the net force:
b. If the desk accelerates at 2.0 m/s2, find the mass of the desk.

Answer 1

Step-by-step explanation:

first and foremost start off with a proper FBD (I drew in the forces and acceleration just to refer back to it quicker, assume right and up are positive)

a) F net = Forces aiding the movement - forces opposing

if the box is sliding to the right then we've got

Fnet = 26 + (-3)

[notice how I wrote that they're both being added because they're vector forces]

Fnet = 23 N

b) using Newton's second law of motion, F = ma, we can find the mass

Fnet = ma

rearrange for mass

M = Fnet/a

M = 23 N / 2.0 ms^-2

M = 11.5 Kg