# Forces in Equilibirum? Star Wars forces?

flyingpig
Forces in Equilibirum? Star Wars forces???

## Homework Statement

http://iweb.tntech.edu/murdock/books/v4chap1.pdf

Go to question 11 where you see three charges hanging.

The solution is something i don't understand.

The forces between the middle and left or right are the same. But the solution also set sum of the force exerted by the middle charge on the left and right on left together to equal to the horizontal force (I think they made a trig mistake, but it worked out fine in this case since $$\theta$$ = 45 degrees).

My question is, how does the right exert a force all the way to the left? This is like Star Wars Forces...

How does it even interact with it?

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My question is, how does the right exert a force all the way to the left? This is like Star Wars Forces...

How does it even interact with it?
They both have a charge, therefore they exert a force on each other. See section 1.1.3 and Equation 1.3.

flyingpig

They both have a charge, therefore they exert a force on each other. See section 1.1.3 and Equation 1.3.

But there is a middle charge that's "blocking"

Mentor

No, charge in the middle doesn't block anything. Whenever you have two charges they either attract or repel each other, no matter what other charges are present around. Thus to solve any question you have to take care of forces between each pair of charges.

Same happens when you have a set of masses (stars, planets) and gravitational forces.