(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that we can calculate the distance of Sirius from us (in Ly) from the above data by two different methods.

If the positions of the Sun and Sirius are interchanged, what will be the m and M values of each?

Sun: m = -26.4; M = +4.6

Sirius: m = -1.4; M = +1.4

2. Relevant equations

M = m + 5 - 5logd

I = L/4pi d^2

I₁/I₂ = L₁/L₂

(d₂/d₁)^2

3. The attempt at a solution

M = m + 5logd

1.4 = -1.4 + 5 - 5logd

1.4 + 1.4 = 5 - 5logd

2.8 = 5 - 5logd

2.8 - 5 = -5logd

-2.2 = -5logd

-2.2/-5 = logd

.44 = logd

Thanks in advance for any help you can offer!

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# Homework Help: Calculating Distance in Two Different Methods

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