DPP-5
Class: 11th
Subject: Physics (NEET/JEE)
Chapter: Gravitation
Topic: Energy, Motion of Satellite
Knowledge Nexus Academy Akola
1. A satellite is to revolve round the earth in a circle of radius (a) 10 (b) 6
8000 km. The speed at which this satellite be projected into (c) Nearly 8 (d) 1.66
an orbit, will be
(a) 3 km / s (b) 16 km / s 9. The ratio of the radius of a planet ‘A’ to that of planet ‘B’
is ‘r’. The ratio of acceleration due to gravity on the planets
(c) 7.15 km / s (d) 8 km / s
is ‘x’. The ratio of the escape velocities from the two
planets is
2. Two satellite A and B, ratio of masses 3 : 1 are in circular
r
orbits of radii r and 4r. Then ratio of total mechanical (a) xr (b)
energy of A to B is x
(a)1 : 3 (b) 3 : 1 x
(c)3 : 4 (d) 12 : 1 (c) rx (d)
r
3. The orbital velocity of a planet revolving close to earth's 10. Time period of revolution of a nearest satellite around a
surface is planet of radius R is T. Period of revolution around another
(a) 2 gR (b) gR planet, whose radius is 3R but having same density is
2g g
(a) T (b) 3T
(c) (d) (c) 9T (d) 3 3 T
R R
4. A satellite moves around the earth in a circular orbit of 11. The ratio of escape velocity at earth ( ve ) to the escape
( v ) whose radius and mean
radius r with speed v. If the mass of the satellite is M, its
total energy is velocity at a planet p
1 1
(a) − 2 𝑀𝑣 2 (b) 2 𝑀𝑣 2 density are twice as that of earth is
3
(c) 𝑀𝑣 2 (d) 𝑀𝑣 2 (a)1: 4 (b) 1: 2
2
(c)1: 2 (d) 1: 2 2
5. A satellite with kinetic energy E k is revolving round the
earth in a circular orbit. How much more kinetic energy 12. Kepler’s third law states that square of period of
should be given to it so that it may just escape into outer revolution (T) of a planet around the sun, is
space proportional to third power of average distance r
(a) E k (b) 2 E k between sun and planet i.e. T = Kr here K is
2 3
1 constant. If the masses of sun and planet are M and
(c) Ek (d) 3 E k
2 m respectively then as per Newton’s law of gravitation
GMm
6. Potential energy of a satellite having mass ‘m’ and rotating force of attraction between them is F = , here
at a height of 6.4 10 6 m from the earth surface is r2
(a) −0.5 mgR e (b) −mgR e G is gravitational constant. The relation between G
(c) −2 mgR e (d) 4 mgR e and K is described as
1
(a) K = G (b) K =
7. When a satellite going round the earth in a circular orbit of G
(c) GK = 4 (d) GMK = 4
radius r and speed v loses some of its energy, then r and v 2 2
change as
(a) r and v both with increase
(b) r and v both will decrease
(c) r will decrease and v will increase
(d) r will decrease and v will decrease
8. The ratio of the radius of the earth to that of the moon is
10. The ratio of acceleration due to gravity on the earth and
on the moon is 6. The ratio of the escape velocity from the
earth's surface to that from the moon is
By Er. Rizwan Ahmad Sir
