JEE Main Physics Gravitation
A focused guide to Newton's law of gravitation, gravitational field and potential, orbital velocity, escape velocity, and satellite motion for JEE Main Physics preparation.
Why Gravitation matters in JEE Main
Gravitation is a key Mechanics chapter. If Newton's law, orbital motion, and energy of satellites are clear, many questions become direct and fast to solve.
What should you know first?
Before solving PYQs, make sure your base concepts are strong. Gravitation is built on force, field, potential, and energy logic.
Core ideas
- Newton's law of gravitationHigh
- Gravitational fieldHigh
- Gravitational potentialHigh
- Orbital velocityHigh
- Escape velocityHigh
Common question areas
- Variation of g with height/depthMedium
- Energy of satelliteHigh
- Kepler's laws applicationHigh
- Binding energyMedium
- Geostationary satelliteMedium
Gravitation formulas to remember
These formulas are essential for solving the chapter quickly and accurately in JEE Main.
| Topic | Formula / Relation | Use case |
|---|---|---|
| Gravitational force | F = Gm₁m₂ / r² | Force between two masses |
| Gravitational field | g = GM / r² | Field due to a mass M |
| Gravitational potential | V = −GM / r | Potential at distance r |
| Orbital velocity | v₀ = √(GM / r) | Velocity of satellite in orbit |
| Escape velocity | vₑ = √(2GM / R) | Minimum velocity to escape |
How to prepare Gravitation smartly
A good strategy is to revise formulas first, then work through solved examples, and finally practise PYQs and mocks.
What to do
- Start with Newton's law and field/potential basics
- Revise orbital and escape velocity formulas
- Practise satellite energy and Kepler's law questions
- Solve previous year questions before moving to mocks
What to avoid
- Do not memorise formulas without understanding r dependence
- Do not skip variation of g with height and depth
- Do not ignore satellite energy and binding energy
- Do not move to mocks before solving chapter questions
What kind of questions appear in JEE Main?
JEE Main usually tests direct application of formulas and orbital motion logic rather than very long derivations.
High frequency patterns
- Orbital velocity and time periodCommon
- Escape velocity comparisonsCommon
- Energy of satellite questionsCommon
- Variation of gFrequent
- Kepler's third law applicationsCommon
Practice tip
- Identify the central body and radiusStep 1
- Choose correct formula (field/potential/energy)Step 2
- Check sign conventions carefullyStep 3
- Track kinetic, potential and total energyStep 4
- Cross-check final unitsStep 5
Gravitation FAQ
Common questions students ask while preparing JEE Main Physics Gravitation.
The most important concepts are Newton's law of gravitation, gravitational field and potential, orbital velocity, escape velocity, and satellite motion based problem solving.
First revise the formulas, then understand gravitational field and potential, practise satellite and orbital motion questions, and finally solve previous year questions and mocks.
Yes, Gravitation is usually scoring when formulas of orbital motion, escape velocity, and energy of satellites are clear.
Important formulas include gravitational force, field and potential, orbital velocity, escape velocity, and energy of a satellite in orbit.