Ok I remeber a question on my physics test. where theres a planet orbiting a star in some other solar system.(adsbygoogle = window.adsbygoogle || []).push({});

heres what was given to me.

the radius,and the time it took for it to finish 1 revolution. I was asked to find the mass of the sun, that the planet was orbiting around

so heres what i did.

I calculated the distance, which was 2 pi r.

I divided that value by time and got the speed.

then i used Fc=FG formula.

mv^2/r = Gm1m2/r^2

with some cancellations, im left with

v^2=Gm(star)/r

so i just isolated for m and solved it. I remember i got like some number x 10^30kg.

but did i do this question right? was this the right method of solving it?

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# Homework Help: How to solve planet orbital question

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