Gravitation

The value of the universal gravitational constant G _______

• Depends on mass of the bodies

• Varies with distance between the bodies
  

• Varies with the medium

• Is a constant everywhere

If the distance between two masses is doubled, the gravitational force between them ________

• Becomes halves

• Becomes one-fourth

• Doubles

• Remains unchanged

If the radius of Earth is reduced to half, keeping the mass unchanged, the acceleration due to gravity will:

• Increase to four times

• Decrease to half

• Remain unchanged

• Decrease to one-fourth

The escape velocity on Earth is approximately

• 7 km/s

• 5 km/s

• 11.2 km/s

• 15 km/s

The orbital velocity of a satellite close to the Earth depends on:

• The mass of the satellite

• The radius of the orbit

• The mass of the Earth

• Both B and C

The gravitational force between two objects is directly proportional to

• Product of their masses

• Square of the distance between them

• Cube of the distance between them

• Reciprocal of the distance between them

Kepler’s third law states that the square of the orbital period of a planet is proportional to

• Square of its distance from the Sun

• Cube of its distance from the Sun

• Fourth power of its distance from the Sun

• Cube root of its distance from the Sun

A geostationary satellite orbits the Earth

• Every 12 hours

• Twice every 24 hours

• Once every 24 hours

• Every 48 hours

Gravitational potential energy at the surface of Earth is

• Zero

• Positive

• Negative

• Infinite

The gravitational force between two identical masses m separated by a distance r is

• Gm²/r

• Gm²/r²

• Gm/r²

• Gm²r²