When a force of 500 N pushes on a 25-kg box, the acceleration of the box up the incline is 0.75 m/s^2. If the inclined plane makes an angle of 40 degrees relative to the horizontal level, what is the coefficient of kinetic friction?

1 answer

M*g = 25 * 9.8 = 245 N. = Wt. of box.

Fp = 245*sin40 = 157.5 N. = Force parallel to the incline.

Fn = 245*Cos40 = 187.7 N = Force perpendicular(normal) to the incline.

Fap-Fp-Fk = M*a.
500-157.5-Fk = 25*0.75, Fk = ?.

k = Fk/Fn