The surface of the sun has a temperature of about 5800K and consists largely of hydrogen atoms.
We're given that the rms speed of a hydrogen atom at this temperature is 1.20*10^4m/s and the escape speed for a particle is 6.20*10^5m/s.
Can appreciable quantities of hydrogen escape from the sun? Can any hydrogen escape?
What fraction of the H atoms have v_z > 6.20*10^5m/s?