# Calculating mass and Schwarzchild radius of Black Hole

1. Oct 14, 2008

### mattst88

1. The problem statement, all variables and given/known data

The temperature of a black hole is given by
$$T = \frac{\hbar c^3}{8 \pi k G M}$$
where h is Planck's constant, k is Boltzmann constant, G is the universal gravitation constant, and M is mass.

Calculate (A) the mass, and (B) the Schwarzchild radius of a black hole at room temperature.

2. Relevant equations

Rearranging the above equation for M,
$$M = \frac{\hbar c^3}{8 \pi k G T}$$

$$r_s = \frac{2 G M}{c^2}$$