Question

Please use the link in the comments (I know if you look it up so please don't cheat)

Calculate the temperature of the Sun.
First, identify the peak wavelength. This is found on the x-axis of the graph, and is measured in micrometers ().

Then use the formula from above to calculate the temperature. Compare your calculation to the temperature given on the graph. They should be close, but won't be exact (I have rounded the constant (2900) so it's a little easier to use).
Calculate the temperature for Sirius A using the same formula. Move the slider on the right side of the screen up to Sirius A. At the top of the y-axis of the graph, press the minus-magnify button twice.

Move the "Blackbody Temperature" slider to 2600K. Find the peak wavelength on the spectrograph, and calculate and verify the temperature.
Without using the simulation.

What is the temperature of a star that has a 0.400 micrometer peak wavelength?

What is the temperature of a star that has a 0.900 micrometer peak wavelength?

Answer 1

Answer:

Sirius A is 1.608 times the size of the Sun.

The radiant flux establishes how much energy an observer or a detector can get from a luminous source per unit time and per unit surface area.

 (1)

Where  is the radiant power received from the source, L is its intrinsic luminosity and r is the distance.

The Stefan-Boltzmann law is defined as:

 (2)

Where  is the radiant power,  is the Stefan-Boltzmann constant and T is the temperature.

Then, equation 2 can be replaced in equation 1

(3)

Notice that L is the energy emitted per second by the source.

Therefore, r can be isolated from equation 3.

 (4)

The luminosity of the Sun can be estimated isolating L from equation 3.

but,  and

To find the luminosity of Sirius A, the following can be used:

Finally, equation 4 can be used to determine the radius of Sirius A.

So, Sirius A has a radius of

Hence, Sirius A is 1.608 times the size of the Sun.

Explanation:

Hope this helps:)  ジョセフ