The normal force depends upon the angle the pushing force is applied to the block. If it is applied parallel to the inclined surface (along the direction of motion), I agree with your equation. Your answer would be in Newtons.
Other force application directions are possible.
An object of mass M = 1,284 g is pushed at a constant speed up a frictionless inclined surface which forms an angle θ = 50 degrees with the horizontal. What is the magnitude of the force that is exerted by the inclined surface on the object?
(I'm using 1.284*9.81*cos50 to get the force but I'm still getting a wrong answer.)
Can anyone explain the steps into solving this kind of problem.
2 answers
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.
In that case,
Positive being up,
-W(of M)+Ncos50=0
=> N=Mg/cos50
plug your numbers, that's your answer.