Class 9 • Physics • Chapter 12
Gravitation
True & False Quiz
Gravity. Float. Pressure.
✓True
✗False
25
Questions
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Ch.12
Chapter
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IX
Class
Why True & False for Gravitation?
How this format sharpens your conceptual clarity
🔵 Gravitation explains why planets orbit the sun, why objects fall, and why we have tides — one of the most powerful and universal forces in nature.
✅ T/F tests Newton's law of gravitation, difference between G and g, free fall, weight vs mass, Archimedes' principle, and buoyancy.
🎯 G (Universal Gravitational Constant) = 6.67 × 10⁻¹¹ N·m²/kg² (constant everywhere); g (acceleration due to gravity) = 9.8 m/s² (varies with altitude and location).
📋
Read each statement carefully. Click True or False — instant feedback with explanation appears. Submit anytime; unattempted questions are marked Skipped.
Q 1
Gravitation is the force of attraction between any two objects in the universe.
Q 2
Newton’s law of gravitation states that gravitational force is proportional to the square of the distance.
Q 3
The acceleration due to gravity is different for all objects on Earth.
Q 4
Weight is the force with which Earth attracts a body.
Q 5
Mass and weight are the same physical quantities.
Q 6
The value of acceleration due to gravity \(g\) is approximately \(9.8\, m/s^2\) on Earth.
Q 7
Buoyancy is a force acting downward on an object immersed in a fluid.
Q 8
According to Archimedes’ principle, buoyant force equals the weight of fluid displaced.
Q 9
A stone will float in water if its weight is less than the buoyant force.
Q 10
The gravitational force between two objects becomes four times if the distance between them doubles.
Q 11
The universal gravitational constant \(G\) has the unit \(Nm^2/kg^2\).
Q 12
The weight of an object is maximum at the equator.
Q 13
The gravitational force depends only on the distance between the objects.
Q 14
Free fall occurs when an object falls under the influence of only gravity without air resistance.
Q 15
Satellites orbit Earth due to gravitational force acting as centripetal force.
Q 16
The gravitational accelerationgggat the center of Earth is zero.
Q 17
Mass of an object changes when taken to Moon.
Q 18
Weight of an object decreases on the Moon compared to Earth.
Q 19
Pressure is force divided by volume.
Q 20
Fluid pressure increases with depth due to weight of fluid above.
Q 21
Thrust is the total force acting on a surface perpendicular to it.
Q 22
Pressure and thrust are the same physical quantities.
Q 23
Gravity only acts on objects moving on Earth’s surface.
Q 24
The Moon’s gravity causes ocean tides on Earth.
Q 25
Archimedes’ principle is valid only for liquids, not gases.
Key Takeaways — Gravitation
Core facts for CBSE Boards & exams
1
Newton's Law of Gravitation: F = Gm₁m₂/r²; force is directly proportional to product of masses, inversely proportional to square of distance.
2
G = 6.67 × 10⁻¹¹ N·m²/kg² (universal constant); g = 9.8 m/s² (acceleration due to gravity on Earth's surface).
3
Weight (W) = mg; unit = Newton (N); varies with location; Mass (m): unit = kg; remains constant everywhere.
4
Free fall: object falling under gravity alone (no air resistance); acceleration = g downward.
5
Archimedes' Principle: upthrust = weight of fluid displaced by the submerged object.
6
Buoyancy: upward force exerted by fluid; object floats if buoyant force ≥ its weight.