CBSE
Multiple Choice QuestionsWhich of the following statements about the gravitational constant is true ?
It is a force
It has no unit
It has same value in all systems of units
It does not depend on the nature of the medium in which the bodies are kept
Acceleration due to gravity is g on the surface of the earth. Then the value of the acceleration due to gravity at a height of 32 km above earth's surface is (Assume radius of earth to be 6400 km)
0.99 g
0.8 g
1.01 g
0.9 g
On an electron in an atom both electric and gravitational forces are collinear we neglect gravitational force (FG) in comparision to electric force (FE ), because
FE > FG
FN > FE
FE >> FG
FN >> FG
A pellet of mass 1 g is moving with an angular velocity of 1 rad/s along a circle of radius 1 m the centrifugal force is
0.1 dyne
1 dyne
10 dyne
100 dyne
The weight of a body on surface of earth is 12.6 N. When it is raised to a height half the radius of earth its weight will be
2.8 N
5.6 N
12.5 N
25.2 N
A satellite orbiting the earth in a circular orbit of radius R completes one revolution in 3 h. If orbital radius of geostationarysatellite is 36,000 km, orbital radius of earth is
6000 km
9000 km
12000 km
15000 km
Two identical solid copper spheres of radius R are placed in contact with each other. The gravitational attraction between them is proportional to
R2
R-2
R4
R-4
Two point objects of masses 1.5 g and 2.5 g respectively area at a distance of 16 cm apart, the centre of gravity is at a distance x from the object of mass 1.5 g where x is
10 cm
6 cm
13 cm
3 cm
The gravitational field is given by E = − xi − 2y2j. When gravitational potential is zero at (0, 0), then the gravitational potential at (2, 1) is
3 unit
6 unit
9 unit
12 unit
If the mass of moon is of earth's mass, its radius is of earth's radius and if g is acceleration due to gravity on earth, then the acceleration due to gravity on moon is
