Class XI CBSE – Revision Questions MCQ – Semester 1

What is the gravitational field strength of a planet when the weight of a 100 kg astronaut is 400 N? a)      ¼ N kg-1   b) 9.8 N kg-1 c) 4 N kg-1  d) infinity   The only natural satellite of the earth complete orbits in about a)      24 days b) 27.3 days c) 30 days … Continue reading Class XI CBSE – Revision Questions MCQ – Semester 1

Why gravitational force of attraction is necessary for a satellite to revolve around earth?

The question was posted by Raj Kumar. The satellite has a velocity. To revolve around, the direction of velocity must change. In the absence of a force it can move only in a straight line. It is the gravitational force which helps the satellite top change direction and revolve around the earth. In other words, for a [...]