Question

A space-ship moves from the earth to the moon and back. The greatest energy required for the spaceship is to overcome the difficulty in

• A. entering the earth's gravitational force
• B. take- off from the earth's field
• C. take- off from the moon field
• D. entering the moon luner surface

Answer 1

The correct option is B take- off from the earth's field

Focus acting on space ship are Gravitational pull due to Earth +Gravitational pull due to mass.

Now since the mass of Earth is greater that mass of moon.

Gravitational pull at Earth's surface would be greater that at Moon's surface.

Hence The space ship will require greatest energy to overcome the difficult in take off from earth's field.