(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

(a) A box is placed on an frictionless inclined plane with an angle of 18° from the horizontal. The box has a mass of 35 kg, what is the magnitude of the acceleration of the box along the inclined plane?

(b) What magnitude of force would you need to apply to the box in order to keep it at rest? Assume there is no friction and the force applied is parallel to the ground.

2. Relevant equations

F=ma

ma=mgsin

3. The attempt at a solution

I got the answer to the first part. I am just confused about the second part. I get that Fnet=0 N in order for the entire system to not move. However, I was thinking that, in order for that to happen, whatever the force would be to begin with, that would have to be the opposing force, as well (i.e. if F=mgsin then for Fnet=0, F=mgsin-mgsin=0, therefore F=mgsin in order for Fnet=0).....but that feels very confusing to me....I know that I have to go against gravity....but...I don't really know how to set up the equation for this problem...

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# Homework Help: Net force to keep box at rest

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