How to Solve for r in the Equation P = (2pG/3)p^2r^2

[james11]

$$P= \frac{2 {\p} G}{3}p^2r^2[\tex]<br /> <br /> i need to find r =<br /> <br /> just having trouble where to start!<br /> <br /> I have tried a few times.<br /> <br /> just a bit stuck!<br /> <br /> Any help would great !<br /> <br /> Thanks in advance$$

 

[james11]

OK let's try again!

$$P= \frac{2 {\p} G}{3}p^2r^2$$

i need to find r =

just having trouble where to start!

I have tried a few times.

just a bit stuck!

Any help would great !

Thanks in advance

 

[jcsd]

Divide both sides by p^2 2G/3

 

[james11]

I have divided by this but i don't seem to get the radius i am given

I end up with R = SQUARE ROOT P2G/3

am i on the track or have mixed up the equation

j

 

[Kelju Ivan]

"I end up with R = SQUARE ROOT P2G/3"
-----

You made a mistake while dividing. You should end up with
$$r^2 = \frac {3P} {2Gp^2}$$

 

[james11]

Yes i have managed to rearrange to and i have that part. The next part of the question ask
to rearrange another equation that is similar to the original equation given but instead it is 2pieG/3*P^2*R^2 and then find R

I have managed to get R = Sqrt3P/2pieGP

any help would be great in pointing me in the right direction

I am not getting the right figure for R so i must messing up this equation
2pieG/3*P^2*R^2



thanks

 

[james11]

I figure it out

My brain must have gone walk abouts for the past week!

j