Thread: Odd net forces in a circle = 0

I proved that all even vectors in a circle than pull outwards have a net force of 0. I'm having trouble with odd vectors.

What I've managed to do so far:



I'm having trouble with doing it for cos, plus I don't know if I'm solving it correctly. Thanks

Originally Posted by RAz

Was this equation given to you?

Wrong factorization.

Well kind of, that is the one I used. We can use any one necessary. We weren't given any equation, we were just asked to prove it.

I proved it for n=3 with real angles, and by adding the vectors it's net force is 0. I also did this for n>3 when n is even. It's when n>3 and odd that I'm having trouble with.

Originally Posted by RAz

Well kind of, that is the one I used. We can use any one necessary. We weren't given any equation, we were just asked to prove it.

I proved it for n=3 with real angles, and by adding the vectors it's net force is 0. I also did this for n>3 when n is even. It's when n>3 and odd that I'm having trouble with.

Is everything supposed to be part of sine function?

Originally Posted by dwsmith

Is everything supposed to be part of sine function?

No it doesn't have to be, as when I was proving when N was even I broke it up.

The question was this: All vectors exert forced of the same magnitude F. Calculate the net force on all the vectors when N is any integer greater than 3.

So yeah, I've done if for N=3 and N>3 when N is even. We can do anything to make it work. Thanks for your help so far ;D

Originally Posted by RAz

No it doesn't have to be, as when I was proving when N was even I broke it up.

The question was this: All vectors exert forced of the same magnitude F. Calculate the net force on all the vectors when N is any integer greater than 3.

So yeah, I've done if for N=3 and N>3 when N is even. We can do anything to make it work. Thanks for your help so far ;D

Use math induction to prove it.
start by showing p(3)
assume p(k)
show p(k+1)