# Simple Black Body Radiation Question

## Homework Statement

The total radiation emitted by a certain star is a factor 16 times that of a second star of equal size. Calculate the ratio between the temperatures of the star.

## Homework Equations

lamda x T = 2.90x10^-3

## The Attempt at a Solution

16I = I

Therefore, Wiens Displacement law (above):
16I x T1 = I x T2
Where I is equal on both sides.

T2/T1 = 16
I'm not too sure on what equations to apply to this! Do I use just Wien's Displacement Law and put them together? Doesn't look right (not supplied with answers).
Or do I use the Stefan Boltzmann Law (I = oT^4)?

How do I know which law to use?
Any help is greatful!

sylas

## Homework Statement

The total radiation emitted by a certain star is a factor 16 times that of a second star of equal size. Calculate the ratio between the temperatures of the star.

## Homework Equations

lamda x T = 2.90x10^-3

## The Attempt at a Solution

16I = I

Therefore, Wiens Displacement law (above):
16I x T1 = I x T2
Where I is equal on both sides.

T2/T1 = 16
I'm not too sure on what equations to apply to this! Do I use just Wien's Displacement Law and put them together? Doesn't look right (not supplied with answers).
Or do I use the Stefan Boltzmann Law (I = oT^4)?

How do I know which law to use?
Any help is greatful!

Just look for the definitions of the Wien's Displacement Law and the Stefan-Boltzmann Law. What are they measuring? What are I, λ and T?