Prove Binary System Brighter by 3/4 Magnitude Than Single Star

[sheepcountme]

I have to prove that a binary system of stars of equal mass, temp, etc. is brighter by a magnitude of 3/4 than a single star of equal mass, temp, etc.

I've been trying to work it out with (m1-m2)=-2.5log(f1/f2)

Might anyone be able to tell me if I am even on the right track?

 

[nicksauce]

Sure. So what's f1/f2 for a binary system versus a single star?

 

[sheepcountme]

Well, f1/f2 for a binary is 1, but how do I compare that to a single star?

 

[nicksauce]

Let me rephrase that. You want to compare the binary system (system 1) to the single star single (system 2). So, let f1 be the flux of the binary system, and let f2 be the flux of a single star. Then what's f1/f2?

 

[sheepcountme]

Ah! so if f1/f2, is 1/.5 it works! Thank you!