Lesson 5.1 – Newton’s Law of Gravitation 

Foundation (Q1–5)

1. State Newton’s law of universal gravitation.

2. Define gravitational force.

3. What does G represent?

4. Write the formula for gravitational force.

5. Is gravitational force attractive or repulsive?

Intermediate (Q6–10)

6. Two masses of 2 kg and 4 kg are 3 m apart. Calculate force.

7. Explain how distance affects gravitational force.

8. State two properties of gravitational force.

9. Describe the effect of doubling one mass.

10. What happens to force if distance is doubled?

Advanced (Q11–15)

11. Derive F = Gm₁m₂/r² using inverse-square law reasoning.

12. Compare gravitational force with electrostatic force.

13. A planet has twice Earth’s mass and same radius. Compare g.

14. Explain gravitational interaction inside a hollow sphere.

15. Analyse gravitational force acting on mass in multi-body system.

Lesson 5.2 – Gravitational Field & Field Intensity 

Foundation (Q1–5)

1. Define gravitational field.

2. What is gravitational field intensity?

3. Write formula g = GM/r².

4. State unit of g.

5. What does g represent on Earth?

Intermediate (Q6–10)

6. Calculate g at 2R from Earth’s centre.

7. Explain why g is less at mountains.

8. Draw gravitational field lines for a point mass.

9. Compare g on Moon and Earth.

10. Explain difference between gravitational force and field.

Advanced (Q11–15)

11. Show relationship between field intensity and potential gradient.

12. Analyse variation of g inside Earth.

13. Prove that g ∝ 1/r² outside a sphere.

14. A planet’s radius doubles but mass same — what happens to g?

15. Explain how Earth’s rotation affects effective g.

Lesson 5.3 – Gravitational Potential & Potential Energy 

Foundation (Q1–5)

1. Define gravitational potential.

2. Why is gravitational potential negative?

3. State formula V = –GM/r.

4. Define gravitational potential energy.

5. Write U = mV.

Intermediate (Q6–10)

6. Calculate potential at 4R from Earth.

7. Find gravitational potential energy for mass at height.

8. Explain potential difference between two points.

9. Sketch graph of V vs r.

10. Compare potential and potential energy.

Advanced (Q11–15)

11. Derive V = –GM/r.

12. Explain significance of potential approaching zero at infinity.

13. Calculate work done in moving satellite between orbits.

14. Analyse potential inside a uniform sphere.

15. Solve multi-step problem involving gravitational potential and energy together.

Lesson 5.4 – Orbital Motion & Satellites 

Foundation (Q1–5)

1. Define orbit.

2. What force provides centripetal force for satellites?

3. State formula for orbital speed.

4. What is orbital period?

5. Define geostationary orbit.

Intermediate (Q6–10)

6. Calculate orbital speed at radius 3R from Earth.

7. Find time period for satellite given radius.

8. Explain why satellites do not fall to Earth.

9. Compare low Earth orbit and high Earth orbit.

10. List uses of geostationary satellites.

Advanced (Q11–15)

11. Derive T = 2π√(r³/GM).

12. Analyse energy distribution of orbiting body.

13. Explain weightlessness using free-fall concept.

14. Calculate change in total energy when orbit radius changes.

15. Solve satellite transfer orbit (Hohmann) conceptual question.

Lesson 5.5 – Escape Velocity & Energy of Orbits 

Foundation (Q1–5)

1. Define escape velocity.

2. State formula vₑ = √(2GM/R).

3. Does escape velocity depend on mass of object?

4. What is binding energy?

5. Distinguish escape velocity and orbital velocity.

Intermediate (Q6–10)

6. Calculate escape velocity for Earth.

7. Explain physical meaning of escape velocity.

8. Compare escape velocity on Moon vs Earth.

9. Draw energy diagram showing bound and unbound states.

10. Explain why astronauts feel weightless during orbit.

Advanced (Q11–15)

11. Derive escape velocity using energy conservation.

12. Analyse escape conditions on planet with double mass and triple radius.

13. Solve multi-step problem involving binding energy.

14. Compare escape velocity for different celestial bodies.

15. Explain why no propulsion is needed to stay in orbit but needed to escape.