The hot glowing surfaces of stars emit energy in the form of electromagnetic rad
ID: 1477569 • Letter: T
Question
The hot glowing surfaces of stars emit energy in the form of electromagnetic radiation. It is a good approximation to assume that the emissivity e is equal to 1 for these surfaces. Part A Find the radius RRigel of the star Rigel, the bright blue star in the constellation Orion that radiates energy at a rate of 2.7×1031W and has a surface temperature of 11,000 K. Assume that the star is spherical. Use =5.67×108W/m2K4 for the Stefan-Boltzmann constant and express your answer numerically in meters to two significant figures.
Explanation / Answer
L = 4*pi*(R^2)sigma(T^4)
where
L is the luminosity, 2.7 *10^31W
e = 1
is the Stefan–Boltzmann constant, = 5.67 *10^-8 W/m^2 k^4
R is the stellar radius = ?
T is the effective temperature = 11000 K
Substituing Values -
2.7 *10^31 = 4*pi*e*(R^2)**(T^4)
2.7 *10^31 = 4*pi*1*(R^2)*5.67 *10^-8*(11000^4)
Solving for R
R = 5.08 * 10^10 m
R = 5.1 * 10^10 m
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.