How exactly do i get fnet of the object in this question...

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To calculate the net force (fnet) on an object, it's essential to understand the forces acting on it, particularly in a system with multiple objects. The net force on an object, such as B, is determined by the difference between the forces exerted by other objects, A and C, which act in opposite directions. The discussion highlights the need to calculate the attractive force between A and C to find the net forces on A and C accurately. Additionally, the relationship fnet = ma is emphasized, but the specific forces must be identified first to apply this equation correctly. Understanding these concepts will clarify how to derive the net force for each object involved.
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Homework Statement


This was an example question done by my teacher but i don't understand how he got the fnet of an object like the yellow part. thanks first time using the forums sorry if i didnt tag this correctly

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Can you be more specific about what it is that you do not understand?
For the net force on B, do you understand the preceding line, giving -1.25 x10-7N? If your question is why that changed into -1x10-7N, I don't know. Looks like a mistake.
There's no working shown for obtaining the other two net forces. How would you calculate those?
 
yeah like how would you solve the question after the gravitational force you get for Fa and Fc. i got lost after the example like i have no idea how he got the fnet of each object. idk how to calculate the fnet... isn't it fnet=ma but what would that do.
 
BlueLine said:
yeah like how would you solve the question after the gravitational force you get for Fa and Fc. i got lost after the example like i have no idea how he got the fnet of each object
Each object experiences a pull from each of the other two, as per the inverse square law formula used.
The net force on B will be the difference between the forces exerted by A and C, since those are pulling in opposite directions.
Your teacher has omitted the calculation for the attractive force between A and C. You will need this to find the net forces on A and C.

Can you calculate the attractive force between A and C?
How would you combine this with forces already calculated to find the net force on A?
 
how exactly do you calculate the fnet for like the object a and c. the mass is 2.. and is the fa suppose to give me the acceleration?
 
Last edited:
BlueLine said:
how exactly do you calculate the fnet for like the object a and c. the mass is 2.. and is the fa suppose to give me the acceleration?
One step at a time. Answer my question about the attractive force between A and C. For this purpose, ignore B.

After that, list the forces acting on A and which way they act. Do they work together or oppose each other?
 
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