Friction, object at rest then accelerates.

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The discussion revolves around calculating the acceleration of a 2.5 kg block on a 53-degree incline with specified static and kinetic friction coefficients. The key point is determining whether the block will slide or remain at rest when released. Initially at rest, the block's movement depends on comparing the gravitational force component along the incline with the maximum static friction force. If the gravitational force exceeds static friction, the block will slide, and kinetic friction will apply. The participants conclude that verifying the forces will clarify the block's motion and lead to the correct acceleration calculation.
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Homework Statement



A 2.5 kg block is on a 53 degres incline for which Uk = 0.25 and Us = 0.5 . Find its acceleration given that (a) it is initially at rest.



I don't know how to approach this. We have kinetic friction when an object slides. This object starts at rest. Does that mean that we will have both kinds of friction in this problem?
 
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It's initially at rest because it is being held there or placed there. As soon as it is released from rest, it will either start to slide, or remain at rest. Can you determine which is the case? It's one or the other, and depending on whether it moves or stays still, that's the value of the friction coefficient you should use.
 
Well I'd go with kinetic friction. As its asking me to find the acceleration , but it could be possible its 0 so I could verify if the force on the block is bigger then Fs which would mean it would slide , which would mean its kinetic only. Well I got it I think. Thank you
 
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EvilBunny said:
Well I'd go with kinetic friction. As its asking me to find the acceleration , but it could be possible its 0 so I could verify if the force on the block is bigger then Fs which would mean it would slide , which would mean its kinetic only. Well I got it I think. Thank you
Yes, you have it!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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