You slide a 15 kg box down a ramp with friction set to an angle of 38°. If the height of the ramp is 1.2 m, what's the frictional force on the box as it gets to the bottom of the ramp if the applied force down the ramp is 52 N?

Respuesta :

Answer:

38.75N

Explanation:

According to Newton's second law

\sum Fx = ma

Fm-Ff = ma

Fm is the moving force

Fm = mgsin theta

Fm = 15(9.8)sin38

Fm = 90.5N

Ff is the frictional force

m is the mass = 15kg

a is two acceleration

Get the acceleration

a= F/m

a = 52/15

a ,= 3.45m/s²

Substitute the given values into the formula

90.5-Ff = 15(3.45)

90.5-Ff = 51.75

Ff = 90.5-51.75

Ff = 38.75N

Hence the frictional force on the box is 38.75N