You might be used to the normal force cancelling out with the weight force, however, this is not always the case. One common example where these forces don’t cancel is objects on inclined planes.
For these questions, there is a component of the weight force which is parallel to and cancels with the normal force, and a component of the weight force which is perpendicular to the normal force and parallel with the slope of the inclined plane. In the diagram below, I’ve indicated this as the net force, however there may also be other forces in the question that need to be considered (e.g. friction, tension in a rope pulling an object up the slope etc.)
It’s important that in these questions you understand all of the forces you need to consider and the directions they act in. Students often get confused here about the direction of the normal force (shown in yellow) and draw it as operating straight up rather than being perpendicular to the surface.
Looking at the equations for the perpendicular and parallel components of the force due to gravity, you can see that
as the angle of the slope increases,
the magnitude of the normal force decreases and
the magnitude of the force component parallel to the slope increases. This matches our real-world understanding that a ball will accelerate faster down a slope that's steeper.
If you’re not sure how I split the force due to gravity into components please review your understanding of vectors and/or ask
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Good luck with physics!!