Question

The Sun’s surface temperature is about 5800 K and its spectrum peaks at 5000 Å. An O-type star’s surface temperature may be 40,000 K. (a) According to Wien’s law, at what wavelength does its spectrum peak? (b) In what part of the spectrum might that peak be? (c) Can the peak be observed with the Keck telescopes on Maunakea in Hawaii? Explain.

Answer 1

Answer:

Part a)

$\lambda_2 = 725 A^o$

Part b)

This range of wavelength exist in the region of X rays

So correct answer will be X Rays

Part c)

No it is not visible because this energy can not travel to large distance

Explanation:

Part a)

As per Wein's law we know that

$\lambda_1T_1 = \lambda_2 T_2$

so we know that

$\lambda_1 = 5000A^o$

$T_1 = 5800 K$

$T_2 = 40,000 K$

now we have

$\lambda_2 = \frac{5000 \times 5800}{40,000}$

$\lambda_2 = 725 A^o$

Part b)

This range of wavelength exist in the region of X rays

So correct answer will be X Rays

Part c)

No it is not visible because this energy can not travel to large distance