Question

A ball is dropped from a spacecraft revolving around the earth at height of 120km . What will happen to ball ?

• A. It will continue to move with the same speed along the original orbit of spacecraft
• B. It will move the same speed , tangentially to the spacecraft
• C. It will fall down to the earth gradually
• D. It will go very far in space

Answer 1

The correct option is A It will continue to move with the same speed along the original orbit of spacecraft

We know that speed of the satellite revolving in orbit of radius $R$,

$v=\sqrt{\frac{GM}{R}}$, Where $G$= Universal Gravitational Constant, $M$ = Mass of the Earth,

When ball is dropped from a spacecraft revolving around the earth at height of 120 Km , Speed of ball is same as speed of spacecraft because ball is in same orbit so it will continue to move with same speed along the original orbit of spacecraft.