Physics Basics – SSC JE Study Notes
(General Awareness & Current Affairs)
Why physics?
Physics is the science that tells us how the world works – from a falling leaf to the power plant that lights your home.
For SSC JE, you just need the basic ideas that appear in daily life and in news about technology, energy or environment.
1. Motion & Force
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Inertia | A book on a table stays still unless you push it. | A ball on a flat floor stays at rest until someone rolls it. |
| Acceleration | A car speeding up or slowing down. | A skateboarder gaining speed when you push the ramp. |
| Force | A shove on a door. | Pushing a shopping cart to make it move. |
Key point – “Force” is a push or pull that changes motion.
2. Work & Energy
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Work | Lifting a suitcase takes effort. | Carrying a bag of groceries a few steps up a staircase. |
| Kinetic Energy | A running runner. | A spinning bicycle wheel. |
| Potential Energy | A book on a shelf (ready to fall). | A stretched rubber band. |
| Conservation of Energy | A swing that never gets higher unless you push it. | A ball rolling down a hill, gaining speed as it loses height. |
Take‑away – Energy is the ability to do work. It can change form but never disappears.
3. Power
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Power | How quickly a battery runs out. | A kettle boiling water in 5 minutes vs. 10 minutes. |
Formula (in plain words) – Power = Work ÷ Time.
“Fast work” means high power.
4. Simple Machines
| Machine | What it does | Tiny Example |
|---|---|---|
| Lever | Moves heavy objects with less effort. | A seesaw at a playground. |
| Pulley | Changes the direction of force. | A flag‑pole flag being raised. |
| Wheel & Axle | Reduces friction. | A bicycle wheel rolling smoothly. |
Tip – Simple machines make work easier in everyday tools.
5. Heat & Temperature
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Temperature | How hot a cup of tea feels. | Feeling the warmth of a sunny day. |
| Heat | Energy that moves from hot to cold. | A heater warming a room. |
| Thermal Conduction | Heat moving through a metal spoon. | Ice melting on a metal tray. |
Rule – Heat moves from hot to cold, not the other way around.
6. Electricity Basics
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Electric Current | Water flowing through a pipe. | The flow of electrons when you turn on a lamp. |
| Voltage | Water pressure that pushes water. | The “push” that makes current flow. |
| Resistance | Narrow pipe that slows water. | A thin wire that heats up. |
| Ohm’s Law | V = I × R (voltage = current × resistance). | If a bulb needs 2 V and 1 A, the resistance is 2 Ω. |
Simple takeaway – Higher voltage or lower resistance → more current.
7. Magnetism
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Magnetic Field | Invisible influence around a magnet. | A magnet pulling a paperclip. |
| North & South Poles | Like the two ends of a bar magnet. | Two magnets sticking together (opposite poles). |
| Electromagnet | Magnet made by an electric current. | A fridge magnet made by a small coil of wire. |
Remember – Same poles repel, opposite poles attract.
8. Waves
| Concept | Everyday Analogy | Tiny Example |
|---|---|---|
| Wave | Ripples on a pond. | Sound waves from a speaker. |
| Frequency |