Help please! simple Physics frictionless crate on ramp problem! Urgent!? A crate of mass m = 100 kg is pushed at constant speed up a frictionless ramp (θ = 30.0°) by a horizontal force F. What are the magnitudes of (a) F and (b) the force on the crate from the ramp? So my teacher did this problem but I do not understand here's what he did: a) mg sin θ = 100(9.8)sin30 = 490 N (I understand this part) 490 / cos30 = 566N <--Why divide by cos 30 to get the correct answer?!? b) N = mg cos θ + F sin θ 100(9.8)cos30 + 566sin30 = 1131N <--I do not understand part b) at all. Can someone explain step by step on what we are doing on part b). help please!