Problem Set #6

Problem set due in class, Feb 26. Show your work.

1) Calculate the main sequence lifetimes for stars of 0.5, 5, 10 and 25 solar masses (4 points).

2) The following table presents the future evolution of the Sun. Calulate the temperature of the Sun and plot its future on an HR diagram (6 points).

3) Two variable stars in a globular cluster have periods of 2 days and 3.5 days. The first star is twice as bright as the second. What are the radii and temperatures for the two stars? (hint: use the mass-luminosity relation for MS stars to get from L to mass) (6 points)