33 Years NEET-AIPMT Chapterwise Solutions - Physics 2020

Gravitation
10. Dependence of intensity of gravitational field (E)
of earth with distance (r) from centre of earth is
correctly represented by
(a) (b)
(c) (d) (2014)
11. Which one of the following plots represents the
variation of gravitational field on a particle with
distance r due to a thin spherical shell of radius R?
(r is measured from the centre of the spherical shell)
(a)
(c)
(b)
(d)
(Mains 2012)
12. Two spheres of masses m and M are situated in air
and the gravitational force between them is F. The
space around the masses is now filled with a liquid
of specific gravity 3. The gravitational force will now
be
(a) 3 F
(b) F
(c) F/3 (d) F/9 (2003)
13. Gravitational force is required for
(a) stirring of liquid (b) convection
(c) conduction (d) radiation (2000)
14. A body of weight 72 N moves from the surface of
earth at a height half of the radius of earth, then
gravitational force exerted on it will be
(a) 36 N
(b) 32 N
(c) 144 N (d) 50 N (2000)
15. Two particles of equal mass m go around a circle
of radius R under the action of their mutual
gravitational attraction. The speed v of each particle
is
(a) 1 2
(c)
1
2R
Gm
R
1
Gm
(b)
(d)
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4Gm
R
Gm
R
(1995)
16. The earth (mass = 6 × 10 24 kg) revolves around
the sun with an angular velocity of 2 × 10 –7 rad/s
in a circular orbit of radius 1.5 × 10 8 km. The force
exerted by the sun on the earth, in newton, is
67
(a) 36 × 10 21 (b) 27 × 10 39
(c) zero (d) 18 × 10 25 (1995)
17. If the gravitational force between two objects were
proportional to 1/R (and not as 1/R 2 ), where R is the
distance between them, then a particle in a circular
path (under such a force) would have its orbital
speed v, proportional to
(a) R (b) R 0 (independent of R)
(c) 1/R 2 (d) 1/R (1994, 1989)
8.5 Acceleration due to Gravity of the Earth
18. If the mass of the Sun were ten times smaller and
the universal gravitational constant were ten times
larger in magnitude, which of the following is not
correct?
(a) Raindrops will fall faster.
(b) Walking on the ground would become more
difficult.
(c) Time period of a simple pendulum on the Earth
would decrease.
(d) g on the Earth will not change. (NEET 2018)
19. A spherical planet has a mass M p
and diameter D p
.
A particle of mass m falling freely near the surface
of this planet will experience an acceleration due to
gravity, equal to
(a)
4GMp
2
Dp
(b)
GMpm
2
Dp
(c) GM p
4GMpm
(d)
2
2
Dp
Dp
(2012)
20. 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 g and that on the surface of the new planet
is g′, then
(a) g′ = g/9 (b) g′ = 27g
(c) g′ = 9g (d) g′ = 3g (2005)
21. The density of a newly discovered planet is twice
that of earth. The acceleration due to gravity at the
surface of the planet is equal to that at the surface of
the earth. If the radius of the earth is R, the radius of
the planet would be
(a) 2R (b) 4R (c)
1
4 R (d)
1
2 R
(2004)
22. The acceleration due to gravity on the planet A is
9 times the acceleration due to gravity on planet B.
A man jumps to a height of 2 m on the surface of A.
What is the height of jump by the same person on
the planet B ?
(a) (2/9) m (b) 18 m
(c) 6 m (d) (2/3) m (2003)