A particle near earth's surface traveling faster than about 11 km/s has enough kinetic energy to completely escape from the earth, despite earth's gravitational pull. Molecules in the upper atmosphere that are moving faster than this will therefore escape if they do not suffer any collisions on the way out.(a) The temperature of earth's upper atmosphere is actually quite high, around 1000 K. Calculate the probability of a nitrogen molecule at this temperature moving faster than 11 km/s, and comment on the result.(b) Repeat the calculation for a hydrogen molecule (H2) and for a helium atom, and discuss the implications.(c) Escape speed from the moon's surface is only about 2.4 km/s. Explain why the moon has no atmosphere.

A particle near earth's surface traveling faster than about 11 km/s has enough kinetic energy to completely escape from the earth, despite earth's gravitational pull. Molecules in the upper atmosphere that are moving faster than this will therefore escape if they do not suffer any collisions on the way out.(a) The temperature of earth's upper atmosphere is actually quite high, around 1000 K. Calculate the probability of a nitrogen molecule at this temperature moving faster than 11 km/s, and comment on the result.(b) Repeat the calculation for a hydrogen molecule (H2) and for a helium atom, and discuss the implications.(c) Escape speed from the moon's surface is only about 2.4 km/s. Explain why the moon has no atmosphere.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter31: Radioactivity And Nuclear Physics

Section: Chapter Questions

Problem 3PE: (a) Repeat Exercise 31.2, and convert the energy to joules or calories. (b) If all of this energy is...

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