Gravitation — DPP 2

20 NEET questions from Gravitation, with answers and explanations. Attempt it as a timed test to get scoring, accuracy breakdown and mistake tracking.

Attempt this test free 20 questions · 30 minutes · +80 marks
1
The gravitational potential energy of a body at a distance r from the center of the earth is U. The force at that point is :
  1. A $\frac { \mathrm { U } } { \mathrm { r } ^ { 2 } }$
  2. B $\frac { U } { r }$
  3. C Ur
  4. D Ur$^{2}$
Show answer & explanation

Correct answer: B

Gravitation – NEET-8826
2
Gravitational potential difference between surface of a planet and a point situated at a height of 20 m above its surface is 2 J/kg. If gravitational field is uniform, then the work done in taking a 5 kg body upto height 4 meter above surface will be :
  1. A 2 J
  2. B 20 J
  3. C 40 J
  4. D 10 J
Show answer & explanation

Correct answer: A

Gravitational field intensity
$\mathrm{E}_{\mathrm{g}}=-\frac{\mathrm{dV}}{\mathrm{dr}}=\frac{2}{20}=0.1$
Hence gravitational force = mE$_{g}$ = 5(0.1) = 0.5N
Work = Force × displacement = (0.5)(4) = 2J
3
A particle falls from infinity to the earth. Its velocity on reaching the earth surface is :
  1. A 2Rg
  2. B Rg
  3. C $\sqrt { \text { Rg } }$
  4. D $\sqrt { 2 \mathrm { Rg } }$
Show answer & explanation

Correct answer: D

Gravitation – NEET-8827
4
Imagine a new planet having the same density as that of earth but its radius 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 :
  1. A $\mathrm { g } ^ { \prime } = 3 \mathrm {~g}$
  2. B $\mathrm { g } ^ { \prime } = \mathrm { g } / 9$
  3. C $\mathrm { g } ^ { \prime } = 9 \mathrm {~g}$
  4. D $\mathrm { g } ^ { \prime } = 27 \mathrm {~g}$
Show answer & explanation

Correct answer: A

Gravitation – NEET-8752
5
The gravitational potential energy is maximum at:
  1. A infinity
  2. B the earth's surface
  3. C The centre of the earth
  4. D Twice the radius of the earth
Show answer & explanation

Correct answer: A

Gravitation – NEET-8823
6
When the radius of earth is reduced by 1% without changing the mass, then the acceleration due to gravity will
  1. A increase by 2%
  2. B decrease by 1.5%
  3. C increase by 1%
  4. D decrease by 1%
Show answer & explanation

Correct answer: A

Gravitation – NEET-8748
7
Potential energy of a 3 kg body at the surface of a planet is -54 J, then escape velocity will be:
  1. A 18 m/s
  2. B 162 m/s
  3. C 36 m/s
  4. D 6 m/s
Show answer & explanation

Correct answer: D

Gravitation – NEET-8895
8
Acceleration due to gravity at earth's surface is 'g' m/s$^{2}$. Find the effective value of acceleration due to gravity at a height of 32 km from sea level : (R$_{e}$ = 6400 Km)
  1. A $0.5 \mathrm {~g} \mathrm {~m} / \mathrm { s } ^ { 2 }$
  2. B $0.99 \mathrm {~g} \mathrm {~m} / \mathrm { s } ^ { 2 }$
  3. C $1.01 \mathrm {~g} \mathrm {~m} / \mathrm { s } ^ { 2 }$
  4. D $0.90 \mathrm {~g} \mathrm {~m} / \mathrm { s } ^ { 2 }$
Show answer & explanation

Correct answer: B

Gravitation – NEET-8750
9
A body attains a height equal to the radius of the earth when projected from earth' surface. The velocity of the body with which it was projected is :
  1. A $\sqrt { \frac { G M } { R } }$
  2. B $\sqrt { \frac { 2 \mathrm { GM } } { \mathrm { R } } }$
  3. C $\sqrt { \frac { 5 } { 4 } \frac { \mathrm { GM } } { \mathrm { R } } }$
  4. D $\sqrt { \frac { 3 \mathrm { GM } } { \mathrm { R } } }$
Show answer & explanation

Correct answer: A

Gravitation – NEET-8825
10
Two small and heavy spheres, each of mass M, are placed a distance r apart on a horizontal surface. The gravitational potential at the mid-point on the line joining the centre of the spheres is :-
  1. A Zero
  2. B $- \frac { \mathrm { GM } } { \mathrm { r } }$
  3. C $- \frac { 2 \mathrm { GM } } { \mathrm { r } }$
  4. D $- \frac { 4 \mathrm { GM } } { \mathrm { r } }$
Show answer & explanation

Correct answer: D

Gravitation – NEET-8829
11
An artificial satellite moving in a circular orbit around the earth has a total (kinetic + potential) energy $\mathrm { E } _ { 0 }$. Its potential energy is :-
  1. A $- \mathrm { E } _ { 0 }$
  2. B $\mathrm { E } _ { 0 }$
  3. C $- 2 \mathrm { E } _ { 0 }$
  4. D $2 \mathrm { E } _ { 0 }$
Show answer & explanation

Correct answer: D

The potential energy of a satellite is equal to twice its total energy.
∴ Potential energy = 2E$_{0}$
12
At some planet 'g' is 1.96 m/sec$^{2}$. If it is safe to jump from a height of 2 m on earth, then what should be the corresponding safe height for jumping on that planet:-
  1. A 5 m
  2. B 2 m
  3. C 10 m
  4. D 20 m
Show answer & explanation

Correct answer: C

Use mg$_{1}$h$_{1}$ = mg$_{2}$h$_{2}$
⇒ (1.96)(h$_{1}$) = (9.8)(2)
⇒ h$_{1}$ = 10 m
13
The acceleration due to gravity g and mean density of earth ρ are related by which of the following relations? [G = gravitational constant and R = radius of earth]:
  1. A $\rho = \frac { 4 \pi \mathrm { gR } ^ { 2 } } { 3 \mathrm { G } }$
  2. B $\rho = \frac { 4 \pi \mathrm { gR } ^ { 3 } } { 3 \mathrm { G } }$
  3. C $\rho = \frac { 3 g } { 4 \pi g R }$
  4. D $\rho = \frac { 3 g } { 4 \pi g R ^ { 3 } }$
Show answer & explanation

Correct answer: C

Gravitation – NEET-8745
14
Which of the following curve expresses the variation of gravitational potential with distance for a hollow sphere of radius R :
  1. A
  2. B
  3. C
  4. D
Show answer & explanation

Correct answer: C

Gravitational potential
$\begin{array}{l}V=\frac{-G M}{r} \text { for } r>R \\ V=\frac{-G M}{R} \text { for } r \leq R\end{array}$
Potential remains constant inside the hollow sphere.
15
A body weighs W newton at the surface of the earth. Its weight at a height equal to half the radius of the earth will be :
  1. A $\frac { W } { 2 }$
  2. B $\frac { 2 W } { 3 }$
  3. C $\frac { 4 W } { 9 }$
  4. D $\frac { W } { 4 }$
Show answer & explanation

Correct answer: C

Gravitation – NEET-8755
16
The change in the value of 'g' at a height 'h' above the surface of the earth is same as at a depth 'd'. If 'd' and 'h' are much smaller than the radius of earth, then which one of the following is correct?
  1. A d = h
  2. B d = 2h
  3. C $d = \frac { 3 h } { 2 }$
  4. D d = $\frac{h}{2}$
Show answer & explanation

Correct answer: B

Gravitation – NEET-8753
17
Two different masses are dropped from same heights. When these just strike the ground, the following is same :
  1. A kinetic energy
  2. B potential energy
  3. C linear momentum
  4. D acceleration
Show answer & explanation

Correct answer: D

Acceleration due to gravity is independent of the mass of object $\mathrm{a}=\frac{\mathrm{GM}_{\mathrm{e}}}{\mathrm{r}^{2}}$
[M$_{e}$ = mass of earth]
18
A particle of mass $m$ is moving in a horizontal circle of radius R under a centripetal force equal to $-\frac{\mathrm{A}}{\mathrm{r}^{2}}$ (A = constant). The total energy of the particle is :- (Potential energy at very large distance is zero)
  1. A $\frac { A } { R }$
  2. B $- \frac { \mathrm { A } } { \mathrm { R } }$
  3. C $\frac { \mathrm { A } } { 2 \mathrm { R } }$
  4. D $- \frac { \mathrm { A } } { 2 \mathrm { R } }$
Show answer & explanation

Correct answer: D

Gravitation – NEET-8831
19
A projectile of mass m is thrown vertically up with an initial velocity v from the surface of earth (mass of earth = M). If it comes to rest at a height h, the change in its potential energy is
  1. A $\mathrm { GMmh } / \mathrm { R } ( \mathrm { R } + \mathrm { h } )$
  2. B $\mathrm { GMmh } ^ { 2 } / \mathrm { R } ( \mathrm { R } + \mathrm { h } ) ^ { 2 }$
  3. C $\mathrm { GMmhR } / \mathrm { R } ( \mathrm { R } + \mathrm { h } )$
  4. D $\mathrm { GMm } / \mathrm { hR } ( \mathrm { R } + \mathrm { h } )$
Show answer & explanation

Correct answer: A

Gravitation – NEET-8828
20
More amount of sugar is obtained in 1 kg weight:
  1. A At North pole
  2. B At equator
  3. C Between pole and equator
  4. D At South pole
Show answer & explanation

Correct answer: B

Gravitation – NEET-8746

Attempt this as a timed test

Reading answers is not the same as sitting the paper. Attempt it timed and you get your score, per-question timing, and the mistakes tracked for revision.

Start free

More Gravitation tests

Gravitation — DPP 1 20 Q Gravitation — DPP 3 20 Q
All Gravitation tests →