Question

Why does Earths moon have no atmosphere? A The average temperature is too high B There are no plants to release oxygen C The moon is too far from earth D the moons gravity is too weak to hold onto gas molecules. 2) On the moon, maria are A merteroid craters B low, flat plains C rough mountains D lunar sears filled with water. 4) Ocean tides are the result of A rotation of Earth B suns gravitiational pull on Earth C changes in earths orbital position around sun D differences in both the sun & moons gravitational pull on earth 5) Which of the following represents an eclipse A when the shadow of-

Answer 1

-the moon is cast on Earths surface. B when the shadow of the moon is cast on the suns surface C when the shadoe of the earth is cast on the moon. D both the first and third choice

Answer 2

The average speed of the molecules of a gas which makes up the atmosphere depends on the mass of the molecules and the temperature.

Whether or not a gas molecule escapes from the gravitation pull of the object depends on the relative sizes of the speed of the molecules and the escape speed from the object. If the speed of the molecule is greater than the escape spedd it will escape from the object.

The escape speed depends on the size (mass and radius) of the object. Lower mass means lower escape speed.

The Earth cannot retain hydrogen and helium in its atmosphere because the escape speed from the Earth is less than the average speed of hydrogen and helium molecules if they were in the atmosphere.

If the temperature increases so the average speed of the gas molecules.