Answer:
Frictional force on the crate by the floor = 300 N
Explanation:
Let's start off by checking how much frictional force acts on the crate by the floor both when it is static, and when it is moving.
Weight of the crate: 180 x 9.81 = 1765.8 N
Lets use the equation: [tex]F = u * R[/tex]
For static friction:
F = 0.4 x 1765.8
F = 706.32 N
For kinetic friction:
F = 0.36 x 1765.8
F = 635.69 N
Since the force we apply (300 N) is less than the static friction on the crate,
the crate will not move. When the crate does not move, the resultant forces acting on it are 0 N. This means that friction is opposing our 300 N force with 300 N frictional force. Thus friction force is 300 N in this situation.