RamanFlame Institute

35. The periodic time of a communication satellite is

(a) 6 hours (b) 12 hours (c) 18 hours (d) 24 hours Answer: d (11)

In the following four periods

(i) Time of revolution of a satellite just above the earth’s surface(Tst) (ii) Period of oscillation of mass inside the tunnel bored along the diameter of the earth(Tma) (iii) Period of simple pendulum having a length equal to the earth’s …

A satellite is to revolve round the earth in a circle of radius 8000 km. The speed at which this satellite be projected into an orbit, will beA satellite is to revolve round the earth in a circle of radius 8000 km. The speed at which this satellite be projected into an orbit, will be

(a) 3 km/s (b) 16 km/s (c) 7.15km/s (d) …

44. A satellite is launched into a circular orbit of radius ‘R’ around earth while a second satellite is launched into an orbit of radius 1.02 R. The percentage difference in the time periods of the two satellites is

(a) 0.7 (b) 1.0 (c) 1.5 (d) 3 Answer: d (43)

42. A geo-stationary satellite is orbiting the earth at a height of 6 R above the surface of earth, R being the radius of earth. The time period of another satellite at a height of 2.5 R from the surface of earth is

(a) 10 hr (b) (6/√2) hr (c) 6 hr (d) 6√2hr Answer: d (4)

40. Periodic time of a satellite revolving above Earth’s surface at a height equal to R, radius of Earth, is [g is acceleration due to gravity at Earth’s surface]

(a) 2π√2R/ g (b) 4√2π√R/g (c) 2π√R/ g (d) 8π√R/ g Answer:b (7)

39. If Gravitational constant is decreasing in time, what will remain unchanged in case of a satellite orbiting around earth

(a) Time period (b) Orbiting radius (c) Tangential velocity (d) Angular velocity Answer: c (3)

38. The distance of a geo-stationary satellite from the centre of the earth (Radius R = 6400 km) is nearest to

(a) 5 R (b) 7 R (c) 10 R (d) 18 R Answer: b (3)

The ratio of the K.E. required to be given to the satellite to escape earth’s gravitational field to the K.E. required to be given so that the satellite moves in a circular orbit just above earth atmosphere is

(a) One (b) Two (c) Half (d) Infinity Answer: b (4)

An astronaut orbiting the earth in a circular orbit 120 km above the surface of earth, gently drops a spoon out of space-ship. The spoon will

(a) Fall vertically down to the earth (b) Move towards the moon (c) Will move along with space-ship (d) Will move in an irregular way then fall down to earth Answer: c (3)

A satellite which is geostationary in a particular orbit is taken to another orbit. Its distance from the centre of earth in new orbit is 2 times that of the earlier orbit. The time period in the second orbit is

(a) 4.8 hours (b) 48√2 hours (c) 24 hours (d) 24 √2 hours Answer: b (3)

Consider a satellite going round the earth in an orbit. Which of the following statements is wrong

(a) It is a freely falling body (b) It suffers no acceleration (c) It is moving with a constant speed (d) Its angular momentum remains constant Answer: b (7)

5. Consider a satellite going round the earth in an orbit. Which of the following statements is wrong

(a) It is a freely falling body (b) It suffers no acceleration (c) It is moving with a constant speed (d) Its angular momentum remains constant Answer: b (6)

An earth satellite of mass m revolves in a circular orbit at a height h from the surface of the earth. R is the radius of the earth and g is acceleration due to gravity at the surface of the earth. The velocity of the satellite in the orbit is given by

(a) gR2/R+h (b) gR (c) gR/R+h (d) √gR2/R+h Answer: d (7)

Select the correct statement from the following

(a) The orbital velocity of a satellite increases with the radius of the orbit (b) Escape velocity of a particle from the surface of the earth depends on the speed with which it is fired (c) The time period of …

If r represents the radius of the orbit of a satellite of mass m moving around a planet of mass M, the velocity of the satellite is given by

(a) v2 = g(M/r) (b) v2 =GMm/r) (c) v =( GM/r ) …

Four particles each of mass M, are located at the vertices of a square with side L. The gravitational potential due to this at the centre of the square is

Answer: a (29)

There are two planets. The ratio of radius of the two planets is K but ratio of acceleration due to gravity of both planets is g. What will be the ratio of their escape velocity

(a) ( Kg )1/2 (b) ( Kg )-1/2 (c) ( Kg )2 (d) ( Kg )-2 Answer:a (4)

The value of escape velocity on a certain planet is 2 km/s. Then the value of orbital speed for a satellite orbiting close to its surface is

(a) 12 km/s (b) 1 km/s (c) √2 km/s (d) 2√2 km/s Answer: c (6)

For a satellite moving in an orbit around the earth, the ratio of kinetic energy to potential energy is

(a) 2 (b) 1/2 (c) 1/√2 (d) √2 Answer: b (7)

If the radius and acceleration due to gravity both are doubled, escape velocity of earth will become

(a) 11.2 km/s (b) 22.4 km/s (c) 5.6 km/s (d) 44.8 km/s Answer: b (6)

If the radius of a planet is four times that of earth and the value of g is same for both, the escape velocity on the planet will be

(a) 11.2 km/s (b) 5.6 km/s (c) 22.4 km/s (d) None Answer: c (4)

The velocity with which a projectile must be fired so that it escapes earth’s gravitation does not depend on

a) Mass of the earth (b) Mass of the projectile (c) Radius of the projectile’s orbit (d) Gravitational constant Answer: b (6)

If V, R and g denote respectively the escape velocity from the surface of the earth radius of the earth, and acceleration due to gravity, then the correct equation is

(a) V=√gR (b) V=√ 4/3 gR 3 (c) V = R√g (d) …

The escape velocity for a body projected vertically upwards from the surface of earth is 11 km/s. If the body is projected at an angle of 45o with the vertical, the escape velocity will be

(a) ( 11/√2 )km/s (b) 11√2km/s (c) 22 km/s (d) 11 km/s Answer: d (3)

Escape velocity on the surface of earth is 11.2 km/s . Escape velocity from a planet whose mass is the same as that of earth and radius 1/4 that of earth is

(a) 2.8 km/s (b) 15.6 km/s (c) 22.4 km/s (d) 44.8 km/s Answer: c (12)

Escape velocity on the earth

(a) Is less than that on the moon (b) Depends upon the mass of the body (c) Depends upon the direction of projection (d) Depends upon the height from which it is projected Answer: d (5)

The escape velocity of a rocket launched from the surface of the earth

(a) Does not depend on the mass of the rocket (b) Does not depend on the mass of the earth (c) Depends on the mass of the planet towards which it is moving (d) Depends on the mass of the …