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nazarfj
A student attaches a rope to a 20.0 kg box of books. He pulls with a force of 90.0 N at an angle of 30.0° with the horizontal and walks to the left. The coefficient of kinetic friction between the box and the sidewalk is 0.500. Find the acceleration of the box. physics please
Draw a picture and label everything you know.
F=m*a 90*cos(30)-0.5*(20)*9.81=20*a a=1.0079m/s^2
Almost, but remember the coefficient of kinetic friction is not the force itself.