PM2017 wrote:Name wrote:1. A star with the same radius and twice the temperature of our sun is found. What is its luminosity (in solar luminosity)?
2. The parallax of a type 1a supernova was found to be .05 milliarcsec. What its distance (in parsecs)?
3. What is the supernovas apparent magnitude?
4. The apparent magnitude of the star in part 1 and the supernova in part 2/3 is the same. What is the distance of the star?
Sorry, I was being lazy and did all this on a computer and no paper or pencil, and I just felt lazy, so lazy in fact that I decided to make this sentence a run on sentence.
1. Stefan boltzmann is sqrt (solar lumo) times (1/solar temp)^2 =solar radius(1). (1/2)^2 is 1/4 or 4= sqrt lumo. Square both sides it's 16 solar lumos.
4. Absolute mag is 1.82, knowing the apparent mag is -2.79 so distance is 1.19 parsecs