Step 2: apply newton's second law apply ∑fy = may , what should ay be equal to, since the block doesn't move in the y direction (perpendicular to the incline surface) at all? obtain an equation involving the normal force fn.

∑Fy = 0, because there is no movement, N = m*g*cos (omega)

Explanation:

We can solve this problem with the help of a free body diagram where we show the respective forces in each one of the axes, y & x. The free-body diagram and the equations are in the image attached.

If the product of mass by acceleration is zero, we must clear the normal force of the equation obtained. The acceleration is equal to zero because there is no movement on the Y-axis.

explanation:

wheres the pic