The orbital angular momentum of a satellite revolving at a distance \(r\)from the centre is \(L\). If the distance is increased to 16r, then the new angular momentum will be:
1. | \(16~L\) | 2. | \(64~L\) |
3. | \(L \over 4\) | 4. | \(4~L\) |
A body of mass m kg starts falling from a point 2R above the Earth’s surface. Its kinetic energy when it has fallen to a point ‘R’ above the Earth’s surface, is:
[R - Radius of Earth, M - Mass of Earth, G - Gravitational Constant] -
1.
2.
3.
4.
A body is projected vertically upwards from the surface of a planet of radius R with a velocity equal to half the escape velocity for that planet. The maximum height attained by the body is:
1. R/3
2. R/2
3. R/4
4. R/5
A satellite is launched into a circular orbit of radius R around the Earth while a second satellite is launched into an orbit of radius 1.02R. The percentage difference in the time periods of the two satellites is:
1. | 0.7 | 2. | 1.0 |
3. | 1.5 | 4. | 3 |
If the gravitational force between two objects were proportional to \(\frac{1}{R}\) (and not as ) where \(R\) is the separation between them, then a particle in circular orbit under such a force would have its orbital speed v proportional to:
1.
2.
3.
4. \(1/R\)
If the acceleration due to gravity at a height 1 km above the earth is similar to a depth d below the surface of the earth, then:
1. d=0.5 km
2. d=1 km
3. d=1.5 km
4. d=2 km
Two astronauts are floating in a gravitational free space after having lost contact with their spaceship. The two will:
1. | keep floating at the same distance between them |
2. | move towards each other |
3. | move away from each other |
4. | will become stationary |
A remote sensing satellite of the earth revolves in a circular orbit at a height of 0.25 x 106 m above the surface of the earth. If the earth’s radius is 6.38x106 m and g=9.8ms-1, then the orbital speed of the satellite is:
1. 7.76 kms-1
2. 8.56 kms-1
3. 9.13 kms-1
4. 6.67 kms-1
The radii of the circular orbits of two satellites A and B of the earth are \(4R\) and \(R,\) respectively. If the speed of satellite A is \(3v,\) then the speed of satellite B will be:
1. | \(3v/4\) | 2. | \(6v\) |
3. | \(12v\) | 4. | \(3v/2\) |
Two satellites A and B go around the earth in circular orbits at heights of respectively from the surface of the earth. Assuming earth to be a uniform sphere of radius , the ratio of the magnitudes of their orbital velocities is:
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