The earth is assumed to be a sphere of radius R. A platform is arranged at a height R from the surface of the earth. The escape velocity of a body from this platform is […]
If the earth shrink such that its mass does not change but radius decreases to one quarter of its original value then one complete day will take
Options
(a) 96 hours (b) 48 […]
The escape velocity of a body from earth’s surface is Ve. The escape velocity of the same body from a height equal to 7R from earth’s surface will be
Options
(a) Ve/√2 (b) […]
A satellite in a circular orbit of radius R has a period of 4 hours. Another satellite with orbital radius 3R around the same planet will have a period (in hours)
Options
(a) […]
If R is the radius of earth, the height at which the weight of a body 1/4 of its weight on the surface of earth.
Options
(a) R (b) 2R (c) R/2 (d) […]
A satellite A of mass m is at a distance r from the centre of earth. Another satellite B of mass 2m is at a distance 2r from the earth centre. Their time periods are […]
Height of geostationary satellite is
Options
(a) 16000 km (b) 22000 km (c) 28000 km (d) 36000 km
Correct Answer:
36000 km
Explanation:
The principle of the geostationary satellite is its period of […]
A body oscillates with amplitude of 10 cm in a horizontal platform. The maximum angular frequency which the platform can vibrate vertically such that body of mass 10 kg will not leave contact is
At what height h above earth, the value of g becomes g/2 (where R=radius of earth)?
Options
(a) (√2-1)R (b) √2R (c) (√2+1)R (d) R/√2
Correct Answer:
(√2-1)R
Explanation:
No explanation available. Be […]
Radius of orbit of satellite of earth is R. Its kinetic energy is proportional to
Options
(a) 1/R (b) 1/√R (c) R (d) 1/R³/²
Correct Answer:
1/R
Explanation:
Kinetic energy of the satellite=1/2mv₀² […]
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