Posted by Michael on .
A physics student is pulling on a 20 kg box that is sliding on the floor. The student applies a pulling force of 100 N using a rope at angle 30o
from the horizontal. The coefficient of kinetic friction between the box and the floor is 0.4. The acceleration of the box is closest to?
Thank you Daemon for all your help! :)

Physics Help, Please 
Damon,
100 cos 30 = horizontal pull = 86.6 N
100 sin 30 = vertical pull = 50 N
Normal force = mg  50 = 146 N
Friction Force = .4*146 = 58.5 N
total horizontal force = 86.658.5 = 28.1 N
F = m a
28.1 = 20 a
a = 1.41 m/s^2