Helppp Astro (1 Viewer)

[SxC]

The star canopus has an aparent magnitude of -0.72 and an absolute magnitude of -3.1

(a)How far away is Canopus in parsecs?

m-M = 5log(d/10)

-0.72-(-3.1) = 5log(d/10)

5log(d/10) = 2.38

then it says (d/10) = 2.99 how did they get that???? i know its a stupid question but can anyone help me urgentlyyy plzzz

 

[wind]

The log in that equation is to the base 10.

So to cancel that you use the notation 10^x rather than e^x.

Is the answer:
d = 29.923 pc?

 

[SxC]

ok so what do u type in da calculator

 

[pc_wizz]

use base 10 ... in the casio caculator use the 'log' button, not the 'ln' button

 

[helper]

og(d/10)=0.476
d/10=inv log (0.476)


To inverse log, hit the inverse key then the log key. The answer should be 2.99

Then times by 10. Answer = 29.9 parsec

 

[wind]

[shift] --> [log]

You'll get a notation looking like 10^x.

Just 10^x both sides of the equation and make "d" the subject to find the distance...simple maths

 

[SxC]

thanx brooo fuck man i always forget da easy shit

 

[lucyinthehole]

shitey you scared me... for a sec i thought this was in space