A projectile is fired from the surface of the earth with a velocity of 5 m s⁻¹ and angle θ with the horizontal. Another projectile fired from another planet with a velocity of 3 m […]
A black hole is an object whose gravitational field is so strong that even light cannot escape from it. To what approximate radius would earth (mass= 5.98×10²⁴ kg) have to be compressed to be a […]
An artificial satellite is revolving round the earth in a circular orbit. Its velocity is half the escape velocity. Its height from earth’s surface is
Options
(a) 6400 km (b) 12800 km (c) […]
Periodic time of a satellite revolving above Earth’s surface at a height equal to R, radius of Earth is (g=acceleration due to gravity at Earth’s surface)
Options
(a) 2π√2R/g (b) 4√2√R/g (c) 2π√R/g […]
Infinite number of masses, each 1 kg, are placed along the x-axis at x= ±1 m, ±2 m, ±4 m, ±8 m, ±16 m ……. The magnitude of the resultant gravitational potential in terms of […]
A siren emitting sound of frequency 800 Hz is going away from a static listener with a speed of 30 m/s. The frequency of sound heard by listener is (velocity of sound = 300 m/s) […]
Suppose for some reasons, radius of earth were to shrink by 1% of present value, mass remaining same, then g(acceleration due to gravity), will change by
Options
(a) Nil (b) 1% (c) -1% […]
In some region, gravitational field is zero. The gravitational potential in this region
Options
(a) Must be variable (b) Must be constant (c) Cannot be zero (d) Must be zero
Correct Answer:
Must […]
A satellite is revolving around the earth with a kinetic energy E. The minimum addition of kinetic energy needed to make it escape from its orbit is
Options
(a) 2E (b) 2/E (c) […]
Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is […]
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