Question

A traveler at Newark airport pulls his 294N suitcase with constant velocity to the check-in counter applying a force of 159N at an angle of 37 degrees with the horizontal. Calculate the Normal force, frictional force and the coefficient of friction between the suitcase and the airport floor.

Answer 1

N = 198.3 N, fr = 126.98 N and μ = 0.64

Step-by-step explanation:

For this exercise we must use the translational equilibrium condition.

Let's set a reference system with the x-axis horizontally and the y-axis vertical. Let's use trigonometry to decompose the applied force

cos θ = Fₓ / F

sin θ = F_y / F

Fₓ = F cos θ

F_y = F sin θ

Fₓ = 159 cos 37 = 126.98 N

F_y = 159 sin 37 = 95.69 N

Y axis

N + F_y - W = 0

N = W - F_y

N = 294 - 95.69

N = 198.3 N

X axis

Fₓ -fr = 0

Fₓ = fr

fr = 126.98 N

the expression for the friction force is

fr = μ N

μ = fr / N

μ = 126.98 / 198.3

μ = 0.64