Class 11 Physics

1. The force of attraction between any two masses in the universe is called:

• A. Gravitational force
• B. Electromagnetic force
• C. Frictional force
• D. Nuclear force

2. Newton's Law of Universal Gravitation states that the gravitational force between two masses is directly proportional to:

• A. The product of their masses
• B. The sum of their masses
• C. The difference of their masses
• D. The square of the distance between them

3. Newton's Law of Universal Gravitation states that the gravitational force between two masses is inversely proportional to:

• A. The square of the distance between them
• B. The product of their masses
• C. The sum of their masses
• D. Time

4. The mathematical formula for Newton's Law of Gravitation is:

• A. F = Gm1m2/r²
• B. F = Gm1m2r²
• C. F = G(m1+m2)/r
• D. F = Gm1m2/r

5. The universal gravitational constant (G) has an approximate value of:

• A. 6.674 × 10⁻¹¹ N m²/kg²
• B. 9.8 m/s²
• C. 3 × 10⁸ m/s
• D. 1.6 × 10⁻¹⁹ C

6. The acceleration produced in a body due to the Earth's gravitational pull is called:

• A. Acceleration due to gravity
• B. Centripetal acceleration
• C. Angular acceleration
• D. Tangential acceleration

7. The value of acceleration due to gravity (g) generally decreases with:

• A. Increasing altitude above the Earth's surface
• B. Decreasing altitude
• C. Increasing mass of the object
• D. Decreasing mass of the object

8. The value of acceleration due to gravity also varies with depth below the Earth's surface, generally:

• A. Decreasing as depth increases
• B. Increasing as depth increases
• C. Remaining constant regardless of depth
• D. Becoming negative

9. Kepler's First Law states that planets move in elliptical orbits with the Sun at:

• A. One of the foci
• B. The exact centre
• C. The circumference
• D. No fixed point

10. Kepler's Second Law states that a line joining a planet and the Sun sweeps out equal areas in equal:

• A. Intervals of time
• B. Distances
• C. Angles
• D. Masses

11. Kepler's Third Law relates the square of a planet's orbital period to the:

• A. Cube of the semi-major axis of its orbit
• B. Square of the semi-major axis
• C. Mass of the planet only
• D. Speed of the planet only

12. The minimum velocity required for an object to escape the Earth's gravitational pull permanently is called:

• A. Escape velocity
• B. Orbital velocity
• C. Terminal velocity
• D. Angular velocity

13. The approximate escape velocity from the Earth's surface is:

• A. 11.2 km/s
• B. 9.8 km/s
• C. 3 km/s
• D. 1 km/s

14. The velocity required for a satellite to maintain a stable circular orbit around a planet is called:

• A. Orbital velocity
• B. Escape velocity
• C. Terminal velocity
• D. Free-fall velocity

15. A satellite that orbits the Earth with the same time period as Earth's rotation is called a:

• A. Geostationary satellite
• B. Polar satellite
• C. Low-orbit satellite
• D. Escape satellite

16. The gravitational potential energy between two masses is generally taken to be:

• A. Negative, with zero potential energy at infinite separation
• B. Always positive
• C. Always zero
• D. Undefined at large distances

17. The weight of an object is defined as the force of gravity acting on its:

• A. Mass
• B. Volume
• C. Density
• D. Surface area

18. Weightlessness experienced by astronauts in orbit occurs because they are in a state of:

• A. Continuous free fall around the Earth
• B. Zero gravity entirely
• C. No gravitational force at all
• D. Complete rest

19. According to the principle of superposition, the net gravitational force on a mass due to several other masses is the:

• A. Vector sum of individual gravitational forces
• B. Scalar sum only
• C. Average of all forces
• D. Product of all forces

20. The value of g at the poles compared to the equator is generally:

• A. Slightly higher at the poles due to Earth's shape and rotation
• B. Equal at both locations
• C. Lower at the poles
• D. Zero at the poles

21. The gravitational field intensity at a point is defined as the gravitational force experienced per unit:

• A. Mass placed at that point
• B. Distance from the source
• C. Time
• D. Volume

22. For a satellite in a low Earth orbit compared to one in a higher orbit, the orbital velocity is generally:

• A. Greater for the lower orbit
• B. Greater for the higher orbit
• C. Equal in both cases
• D. Independent of orbital radius

23. The time period of a geostationary satellite is approximately:

• A. 24 hours
• B. 12 hours
• C. 90 minutes
• D. 1 hour

24. The gravitational force between two objects becomes four times weaker if the distance between them is:

• A. Doubled
• B. Halved
• C. Tripled
• D. Quadrupled

25. Which scientist first proposed the law of universal gravitation?

• A. Isaac Newton
• B. Johannes Kepler
• C. Galileo Galilei
• D. Albert Einstein

26. The path of a projectile with very high velocity, when considering Earth's curvature, can become:

• A. An orbital path around the Earth
• B. A straight vertical line only
• C. A stationary point
• D. Impossible to determine

27. The value of acceleration due to gravity on the Moon is approximately what fraction of Earth's gravity?

• A. 1/6
• B. 1/2
• C. Equal to Earth's
• D. Twice Earth's

28. If the mass of one object in a gravitational interaction is doubled while distance remains constant, the gravitational force:

• A. Doubles
• B. Halves
• C. Remains unchanged
• D. Quadruples

29. The centripetal force required for a satellite's circular orbit around the Earth is provided by:

• A. The gravitational force of attraction between the Earth and satellite
• B. Air resistance
• C. The satellite's own engine continuously
• D. Magnetic forces

30. Which of the following best explains why astronauts float inside the International Space Station?

• A. Both the station and astronauts are in continuous free fall, experiencing effective weightlessness
• B. There is no gravity at all in that region of space
• C. The astronauts have lost all mass
• D. The station is stationary relative to Earth