can any one show me hwo to do this physics?

Question

a force of 531 at -40 degrees newtons is required to give a 160 kg mass an acceleration of 1.31 m/s^2 . what is the force produced by the kinetic friction? what is the coefficient of kinetic friction?

Answer 1

Let us say that the angle is with respect to the normal of the mass, than the force applied is 531cos(40 Degrees).

(160*1.31) = 531*cos(40 Degrees) - 160*mu_k*displacement

Answer 2

It's necessary to know whether the 160 kg mass is accelerating horizontally or perhaps down a -40 degree slope (a standard position angle measured CLOCKWISE, because of the negative, with respect to a positive horizonal x axis)