Gravitation: Master Newton's Laws and Celestial Mechanics

Question 1

Which of the following is NOT a consequence of Newton's Law of Universal Gravitation?

Accepted Answer

The force of gravity is a contact force.

Answer

The force of gravity between two objects is directly proportional to their masses.

Answer

The force of gravity between two objects acts along a line joining their centers.

Answer

The force of gravity between two objects is inversely proportional to the square of the distance between them.

Question 2

According to Newton's law of universal gravitation, the gravitational force between two point masses depends on which of the following factors?

Accepted Answer

Both the masses of the objects and the distance between them

Answer

The masses of the objects

Answer

The distance between the objects

Answer

Neither the masses of the objects nor the distance between them

Question 3

The escape velocity from the surface of a planet is defined as the minimum velocity required to:

Accepted Answer

Overcome the gravitational pull of the planet and travel to outer space

Answer

Put an object into stable orbit around the planet

Answer

Reduce the object's weight to zero

Answer

Achieve a constant velocity

Question 4

According to Newton's law of universal gravitation, the gravitational force between two point masses is directly proportional to their:

Accepted Answer

Masses

Answer

Distances squared

Answer

Volumes

Answer

Densities

Question 5

The gravitational field strength at a point is defined as the:

Accepted Answer

Force experienced by a unit mass at that point

Answer

Acceleration due to gravity at that point

Answer

Potential energy per unit mass at that point

Answer

Gravitational constant at that point

Question 6

The gravitational force between two protons is approximately:

Accepted Answer

10^36 times weaker than the electrostatic force

Answer

10^36 times stronger than the electrostatic force

Answer

Equal to the electrostatic force

Answer

Zero

Question 7

The path of a projectile in a gravitational field is a:

Accepted Answer

Parabola

Answer

Straight line

Answer

Circle

Answer

Hyperbola

Question 8

The period of a satellite's orbit around the Earth is independent of its:

Accepted Answer

Mass

Answer

Orbital radius

Answer

Gravitational constant

Answer

Orbital shape

Question 9

Newton's Law of Universal Gravitation describes the force between two objects due to their mass. Which equation correctly represents this force (F) for objects with masses m and M, separated by a distance R?

Accepted Answer

F = G * (m * M) / R²

Answer

F = G * (m + M) / R²

Answer

F = G * (m * M) / R

Answer

F = G * (m / M) / R²

Question 10

Which of the following factors does NOT affect the strength of the gravitational force between two objects?

Accepted Answer

Temperature of the objects

Answer

Masses of the objects

Answer

Distance between the objects

Answer

Presence of other gravitational fields

Question 11

Which of the following exerts the strongest gravitational pull on Earth?

Accepted Answer

Sun

Answer

Jupiter

Answer

Moon

Answer

Mars

Question 12

According to Newton's law of universal gravitation, the force of gravity between two objects is directly proportional to:

Accepted Answer

The product of their masses

Answer

The difference of their masses

Answer

The sum of their masses

Answer

The square of their distances

Question 13

Gravitational field strength at a point is defined as the:

Accepted Answer

Force experienced by a unit mass placed at that point

Answer

Mass of the object creating the field

Answer

Distance from the object creating the field

Question 14

The acceleration due to gravity near the Earth's surface is approximately:

Accepted Answer

9.8 m/s²

Answer

6371 km

Answer

6.67 x 10⁻¹¹ m³/kg s²

Answer

3.14 m/s²

Question 15

The weight of an object on Earth refers to the:

Accepted Answer

Force of gravity acting on it

Answer

Acceleration due to gravity

Answer

Mass of the object

Question 16

The gravitational potential energy of an object at a height 'h' above the Earth's surface is given by:

Accepted Answer

mgh

Answer

h/mg

Answer

mg/h

Answer

1/2 mgh²

Question 17

The escape velocity from the Earth's surface is approximately:

Accepted Answer

11.2 km/s

Answer

9.8 m/s

Answer

108,000 km/h

Answer

39600 km/h

Question 18

The primary factor responsible for the motion of planets around the Sun is:

Accepted Answer

Gravitational force

Answer

Nuclear force

Answer

Magnetic force

Answer

Electrostatic force

Question 19

The occurrence of tides is primarily attributed to:

Accepted Answer

Gravitational pull exerted by the Moon and the Sun

Answer

Rotation of the Earth

Answer

Electromagnetic radiation from the Moon and the Sun

Question 20

A satellite orbits the Earth at a constant speed. Which statement about the gravitational force acting on the satellite is TRUE?

Accepted Answer

The gravitational force remains constant.

Answer

The gravitational force increases with time.

Answer

The gravitational force fluctuates randomly.

Answer

The gravitational force decreases with time.

Question 21

Two objects, A and B, are separated by a distance 'r'. If the mass of object A is doubled, what happens to the gravitational force between them?

Accepted Answer

The gravitational force doubles.

Answer

The gravitational force remains the same.

Answer

The gravitational force is halved.

Answer

The gravitational force quadruples.

Question 22

A planet has a mass of 2M and a radius of R. What is the gravitational acceleration at the surface of this planet? (G represents the gravitational constant)

Accepted Answer

2GM/R^2

Answer

GM/2R^2

Answer

4GM/R^2

Answer

GM/R^2

Question 23

A spacecraft is in orbit around a planet. If the spacecraft's orbital radius is increased, what happens to its orbital period?

Accepted Answer

The orbital period increases.

Answer

The orbital period decreases.

Answer

The orbital period remains the same.

Answer

The orbital period changes unpredictably.

Question 24

What is the primary reason for the extreme gravitational pull of a black hole?

Accepted Answer

An incredibly dense mass concentrated in a small volume.

Answer

The presence of dark matter.

Answer

The absence of any electromagnetic radiation.

Answer

A strong magnetic field generated within the black hole.

Question 25

Which of the following is NOT a direct consequence of the gravitational force?

Accepted Answer

The emission of light from a star.

Answer

The tides on Earth.

Answer

The orbits of planets around the Sun.

Answer

The formation of galaxies.

Question 26

Two objects of equal mass are placed at a certain distance apart. If the distance between them is doubled, what happens to the gravitational force between them?

Accepted Answer

Decreases by a factor of four.

Answer

Increases by a factor of four.

Answer

Decreases by a factor of two.

Answer

Remains the same.

Question 27

A geostationary satellite orbits the Earth at a specific altitude. What is the primary reason for this specific altitude?

Accepted Answer

To maintain a constant position relative to a point on Earth.

Answer

To avoid collisions with other satellites.

Answer

To maximize the satellite's orbital speed.

Answer

To minimize the gravitational force acting on the satellite.

Question 28

Two planets, A and B, have masses M and 2M respectively. They are separated by a distance 'd'. At what point between them would the gravitational field be zero?

Accepted Answer

At a point closer to planet A, at a distance 'd/3' from A.

Answer

At the midpoint between the two planets.

Answer

The gravitational field cannot be zero at any point between the planets.

Answer

At a point closer to planet B, at a distance 'd/3' from B.

Question 29

A hypothetical planet has a mass of 10^24 kg and a radius of 5 x 10^6 m. What is the escape velocity from this planet's surface? (G = 6.67 x 10^-11 Nm^2/kg^2)

Accepted Answer

Approximately 11.2 km/s.

Answer

Approximately 5.6 km/s.

Answer

The escape velocity cannot be determined with the given information.

Answer

Approximately 22.4 km/s.