Gravitation - Practice Test, Class 9 Science - Class 9 MCQ

The atmosphere is held to the earth by

The value of acceleration due to gravity

Law of gravitation gives the gravitational force between

The value of ‘g’ at a particular point is 9.8 m/sec² suppose the earth suddenly shrink uniformly to half its present size without losing any mass. The value of ‘g at the same point (assuming that the distance of the point from the centre of the earth does not shrink) will become

If the radius of the earth were to shrink by 1% its mass remaining the same, the acceleration due to gravity on the earth’s surface would

There is no atmosphere on the moon because

The period of geostationary artificial satellite is

A missile is launched with a velocity less than the escape velocity. The sum of its kinetic and potential energy is

If the earth is 1/4^th of its present distance from the sun, the duration of the year would be

The period of a satellite in a circular orbit of radius R is T. The period of another satellite in circular orbit of radius 4R is

Who among the following first gave the experimental velocity of G?

Geo-stationary satellite

The dimensions of universal gravitational constant are

The radii of the earth and the moon are in the ratio 10 : 1 while acceleration due to gravity on the earth’s surface and moon’s surface are in the ratio 6 : 1. The ratio of escape velocities from earth’s surface to that of moon surface is

When body is raised to a height equal to radius of earth, the P.E. change is

The masses of two planets are in the ratio 1 : 2. Their radii are in the ratio 1 : 2. The acceleration due to gravity on the planets are in the ratio.

If g is the acceleration due to gravity of the earth’s surface the gain in the potential energy of an object of mass m raised from the surface of the earth to a height equal to the radius R of the earth is