Equation help please

Yes, I do not really understand your problem either, you can put it straight into a calculator but maybe you want to understand the scientific notation better??

\(2.8*10^{30}(1.29*10^{14}/(1.35*10^{11})\\ =2.8*10^{30}*\frac{1.29*10^{14}}{1.35*10^{11}}\\ =(2.8*1.9 / 1.35)\;\;\;*\;\;\;10^{30}*\frac{10^{14}}{10^{11}}\\ =(2.8*1.9 / 1.35)\;\;\;*\;\;\;10^{30+14-11}\\ =3.94074\;\;\;*\;\;\;10^{33}\\\)

You have already given the formula, namely:

Mass of planet = mass of star (Amplitude * speed of light/radius)

If you have the: Mass of the star: Amplitude: Speed of light: Radius, then it should be very simple to calculate. I don't see the speed of light in your calculations. If you give me just the, mass of star, amplitude, and the radius, then I can help you get the right answer.

Hi

Thanks for the replies.

Ill provide for information.


I'm using the formula Mp = Mstar (Ac/r)

I know that Mstar = 2.8e30kg

I know the Radius of the planet = 1.35e11m  (This is how far the planet is from the star)
The amplitude (A) I have is 432km (converted to 432e+5m)
The speed of light (c) is 2.998e8m/s


So based off my formula It should be

Mass Of Planet = 2.8e30 X (4.32e5/1.35e11)

The answer I get = 8.96e24

Am I doing this correctly?
 

Yes, it's right the way you have calculated. The only thing I don't see is the speed of light, in your calculations. The answer that you got is very close to the mass of an average planet like Earth.

Ok, this is progress then, thank you.

Ac in my formula is Amplitude * Speed of light = 4.32e5

Amplitude = 432km (converted to 432e+5m)
Speed of light = 2.998e8m/s

Correct?

OK. I think I know what you have done and it looks right.

I submitted my answer and it was correct. Thank you for your quick replies. I only have a certain number of attempts for each question in the lesson. So Im being over paranoid. Thanks!

You are doing just fine. Congrats and keep it up.