General Astronomy - Spring
2011
Homework #8 - due March 28
1. (4 pt)
Calculate
the fractional gravitational redshift for light emitted from the
surface of a star with a mass of 10 solar masses and a radius of one
Earth radius.
2. (3 pt) What is the Schwarzschild radius
of a
3,000,000
solar mass black hole?
3. (4 pt) What is the maximum possible amount of energy which could be
released by dropping 1 kg of hydrogen gas onto a maximally rotating
black hole?
4. (3 pt) A black hole is observed at a luminosity of 1033
W.
What does this tell us about the black hole mass?
5. (6 pt) Calculate the peak temperature of the blackbody radiation
from a 100
solar mass black hole radiating at the Eddington luminosity.