Solve FBD Problem: M.asinθ=N, N.sinθ=Ma

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The discussion revolves around solving a force balance diagram (FBD) problem involving equations related to forces and accelerations. The user questions the correctness of their derived equations, particularly focusing on whether M.asinθ=N and N.sinθ=Ma are valid. It is clarified that the absence of gravitational force (g) in the provided diagram makes one of the equations incorrect. The user acknowledges the need for a more detailed problem description and admits that their new equations are not useful for deriving relations. Ultimately, the conversation emphasizes the importance of accurately representing forces and components in FBD problems.
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Homework Statement



see attached image

Homework Equations



F=ma

The Attempt at a Solution


I have the relations
1)M.asinθ=N
2)N.sinθ=Ma
Which one is correct and why?
3)if (1) is incorrect is the correct relation --M.asinθ+M.gcosθ=N?
 

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Forces and accelerations are vectors. Once you have Newton's second law in the vector form, you obtain equations for the components of forces and accelerations. In this case, you only care about the horizontal components. What are they?
 
horizontal components
of acc. are-- a and (nsinθ)/m
and force are-- ma and nsinθ
but my main question is that is my equation 3 correct?
 
hav0c said:
horizontal components
of acc. are-- a and (nsinθ)/m
and force are-- ma and nsinθ

It is not that "a and (nsinθ)/m" are "acceleration components". a = (nsinθ)/m is the horizontal acceleration component.

but my main question is that is my equation 3 correct?

I do not see any "g" in the picture so based solely on the picture, that equation is definitely wrong.
 
voko said:
I do not see any "g" in the picture so based solely on the picture, that equation is definitely wrong.
I have taken g to be the acceleration downwards due to gravity
 
Perhaps you need to describe your problem in full detail. What you have now makes little sense.
 
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from here i have got the relations
1)N=M.g.cosθ+M.a.sinθ
2) a.cosθ=g.sinθ

Edit:i have forgotten to consider the normal force from underneath , I'm going to re-write the equations
Edit: nevermind these equations are totally useless
 

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Last edited:
hav0c said:
Edit: nevermind these equations are totally useless
As are the diagrams. Please state the question exactly as it was given to you.
 
I wasnt having any actual problem in solving questions it was just that i wanted to check whether or not i could derive relations by using different x-y directions, but the new general equations turned out to be useless.
 
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