Hydrogen is in abundance around the sun
- Hydrogen is in abundance around the sun but not around earth. Why?
ANSWER: The escape velocity on the sun is very high compared to that on the earth. The gravitational pull of the sun is very large because of its larger mass compared to that of the earth. So it is very difficult for hydrogen to escape from the sun's atmosphere because r.m.s velocity of hydrogen is more than escape velocity(11.2 km/sec). But on the sun r.m.s velocity of the hydrogen is less than the escape velocity of the sun. Hence hydrogen is abundant on sun.
- r.m.s velocity means root mean square velocity)
- escape velocity of the planet/star is the minimum velocity required to a body to escape form the planet/star.