Question

An object of mass M = 1,338 g is pushed at a constant speed up a frictionless inclined surface which forms an angle θ = 50 degrees with the horizontal. Incline is increasing. What is the magnitude of the force that is exerted by the inclined surface on the object?

Answer 1

Again, what is the normal force of weight?

Answer 2

Tilt your axis such that, Y is pointing to the opposite of Weight of M. And X is pointing towards the right. (like usual). [The axis shown in the diagram requires you to find Fnet, which I don't know how to find; thus use this method].

In that case,

Positive being up,

-W(of M)+Ncos50=0
=> N=Mg/cos50

plug your numbers, that's your answer.