In a try to test my knowledge of Newton's laws, I have posed the following question to myself.(adsbygoogle = window.adsbygoogle || []).push({});

My attempt: Object A | Object B | Object C

Object A pushes on B by an amount of 60N

Object B pushes on A by an amount of 30N

Object C pushes on B by an amount of 10N

What is the resultant force of each object?

(The arrows indicate direction.)

I have been informed that the solution is invalid, and that the question itself is wrong. Can you tell me why the problem is wrong/invalid? Considering A and B:

A pushes on B by 60, so F_AonB = 60→

B reacts on A by 60, so F_BonA = 60←

B pushes on A by 30, so F_BonA becomes 90←

A reacts on B by 30, so F_AonB becomes 90→

Considering B and C:

C pushes on B by 10, so F_ConB = 10←

B reacts on C by 10, so F_BonC = 10→

Considering A and B (after considering C on B):

B pushes on A by 100, so F_BonA = 100←

A reacts on B by 100, so F_AonB = 100→

Conclusion:

A pushes 100→

B pushes 100← and 10→

C pushes 10←

Someone tried to explain to me, but I didn't really understand.

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# Question about analyzing forces

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