Question

When Emma pushes a bag with a force of 27 newtons, the coefficient of kinetic friction between the bag and the floor is 0.23. What is the normal force acting on the bag by the floor?

Answer 1

Normal force(N) is always equal and opposite to the weight.
The floor is exerting an upward force upon the bag in order to support the weight of the bag.
Friction force is proportional to the normal force:
f = k * N
In this case: f=27 N, k=0.23
27 N = 0.23 * N
N= 27 N : 0.23 = 117.39 N