The mass of a planet is $$\left ( \dfrac{1}{10} \right )^{\text{th}}$$ that of the earth and its diameter is half that of the earth. The acceleration due to gravity on that planet is:
 1 $$9.8 ~\text{ms}^{-2}$$ 2 $$4.9 ~\text{ms}^{-2}$$ 3 $$3.92 ~\text{ms}^{-2}$$ 4 $$19.6~\text{ms}^{-2}$$
Subtopic:  Acceleration due to Gravity |
62%
From NCERT
NEET - 2024
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The minimum energy required to launch a satellite of mass $$m$$ from the surface of earth of mass $$M$$ and radius $$R$$ in a circular orbit at an altitude of $$2R$$ from the surface of the earth is:
 1 $$\dfrac{2 G m M}{3 R}$$ 2 $$\dfrac{G m M}{2 R}$$ 3 $$\dfrac{G m M}{3 R}$$ 4 $$\dfrac{5 G m M}{6 R}$$
Subtopic:  Satellite |
From NCERT
NEET - 2024
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A rocket is fired vertically upward with a speed of $$\dfrac{v_e}{\sqrt2}$$ from the earth's surface, where $$v_e$$ is escape velocity on the surface of earth. The distance from the surface of earth upto which the rocket can go before returning to the earth is
(Given radius of earth $$=6400~\text{km}$$ ):
 1 $$1600~\text{km}$$ 2 $$3200~\text{km}$$ 3 $$6400~\text{km}$$ 4 $$12800~\text{km}$$
Subtopic:  Escape velocity |
60%
From NCERT
NEET - 2024
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A body weighing $$100~\text{N}$$ on the surface of earth weights $$x~\text{kg-ms}^{-2}$$ at a height $$\dfrac{1}{9} R_E$$ above the surface of earth. The value of $$x$$ ($$g= 10~\text{ms}^{-2}$$ at surface of earth and $$R_E$$ is the radius of earth):
1. $$72$$
2. $$54$$
3. $$81$$
4. $$62$$
Subtopic:  Acceleration due to Gravity |
77%
From NCERT
NEET - 2024
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The escape velocity for Earth is $$v.$$ A planet having $$9$$ times the mass of Earth and a radius, $$16$$ times that of Earth, has the escape velocity of:
 1 $$\dfrac{v}{3}$$ 2 $$\dfrac{2v}{3}$$ 3 $$\dfrac{3v}{4}$$ 4 $$\dfrac{9v}{4}$$
Subtopic:  Escape velocity |
78%
From NCERT
NEET - 2024
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An object of mass $$100 ~\text{kg}$$ falls from point $$A$$ to $$B$$ as shown in the figure. The change in its weight, corrected to the nearest integer is ($$R_E$$ is radius of the earth):

1. $$49~\text N$$
2. $$89~\text N$$
3. $$5~\text N$$
4. $$10~\text N$$
Subtopic:  Acceleration due to Gravity |
56%
From NCERT
NEET - 2024
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Two bodies of mass $$m$$ and $$9m$$ are placed at a distance $$R$$. The gravitational potential on the line joining the bodies where the gravitational field equals zero, will be: ($$G$$ = gravitational constant)
1. $$-\dfrac{20~Gm}{R}$$
2. $$-\dfrac{8~Gm}{R}$$
3. $$-\dfrac{12~Gm}{R}$$
4. $$-\dfrac{16~Gm}{R}$$
Subtopic:  Gravitational Potential |
52%
From NCERT
NEET - 2023
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A satellite is orbiting just above the surface of the earth with period $$T.$$ If $$d$$ is the density of the earth and $$G$$ is the universal constant of gravitation, the quantity $$\frac{3 \pi}{G d}$$ represents:
1. $$\sqrt{T}$$
2. $$T$$
3. $$T^2$$
4. $$T^3$$
Subtopic:  Satellite |
67%
From NCERT
NEET - 2023
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The escape velocity of a body on the earth's surface is $$11.2$$ km/s. If the same body is projected upward with a velocity $$22.4$$ km/s, the velocity of this body at infinite distance from the center of the earth will be:
 1 $$11.2\sqrt2$$ km/s 2 zero 3 $$11.2$$ km/s 4 $$11.2\sqrt3$$ km/s
Subtopic:  Escape velocity |
From NCERT
NEET - 2023
If $$R$$ is the radius of the earth and $$g$$ is the acceleration due to gravity on the earth surface. Then the mean density of the earth will be:
 1 $$\dfrac{\pi RG}{12g}$$ 2 $$\dfrac{3\pi R}{4gG}$$ 3 $$\dfrac{3g}{4\pi RG}$$ 4 $$\dfrac{4\pi G}{3gR}$$