How to Convert Units for Finding the Mass of a Star?

[leonne]

Homework Statement

Need help with some unit conversion. The problem asks to find mass of a star.
p=1.58e9 seconds a=7.61" d=8.15e18 cm +-.001

Homework Equations

M=(4pie^2 d^3 a^3)/Gp^2

The Attempt at a Solution

My problem is with " arcsecond i think it is. The mass should be 5.967e33 grams about. I tried converting it into degrees but get a huge number.

 

[granpa]

http://www.wolframalpha.com/input/?i=7.61"+in+degrees

 

[leonne]

hey i know used the degree and got total mass as 3541 solar mass and only should be 3 solar mass, so something must be wrong idk wht
thxs anyways

 

[granpa]

I can't help you because I have no idea where you are getting your equation.
Did you determine the equation yourself or was it a given

period of what
angle of what
distance from what to what

 

[leonne]

thats the formula to find center of mass for a star distance is between the two star period is how long it takes for a rotation

 

[leonne]

nvm i think i got it, i think i convert it into radians

 

[granpa]

whats the angle

 

[leonne]

well when i used 3.689e-5 rad for the semi-major axes (a) that gave me a much better answer still have the masses off by as little but my numbers are little different from what wiki has so should be all good. thxs