📚 Bihar TET – General Awareness & Current Affairs
Topic: Physics Basics
Physics is the natural science that studies matter, energy, and the fundamental forces of the universe. In the TET syllabus, only the conceptual fundamentals are required – no heavy calculations.
1️⃣ Simple Explanation
| Concept | What it means | Everyday example |
|---|---|---|
| Physics | The science of motion, energy, forces, waves, heat, electricity, magnetism, and the structure of matter. | A ball rolling down a hill (motion & force). |
| Fundamental Units | SI units – metre (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), candela (cd). | 1 m = 100 cm, 1 s = time of one second. |
| Newton’s Laws | 1) Inertia, 2) F = ma, 3) Action = Reaction. | A book at rest stays at rest until you push it. |
| Energy | Capacity to do work (kinetic, potential, thermal, electrical, nuclear). | A moving car has kinetic energy. |
| Waves | Disturbance that propagates energy (mechanical or electromagnetic). | Sound traveling through air. |
| Electricity & Magnetism | Electric current flows in conductors; changing magnetic fields induce currents. | A toaster uses electric current. |
| Thermodynamics | Laws governing heat transfer, temperature, and energy conversion. | Ice melts because heat flows into it. |
| Modern Physics | Relativity & quantum mechanics – concepts like mass–energy equivalence, photon, electron. | Light bending around the Sun (relativity). |
2️⃣ Key Points (Bullet‑style)
| Area | Key Take‑aways |
|---|---|
| Units & Symbols | 1 m, 1 kg, 1 s, 1 A, 1 K, 1 mol, 1 cd. Use SI for all calculations. |
| Newton’s Laws | • Law 1: An object stays in its state of motion. • Law 2: (F = m a). • Law 3: Forces always come in pairs. |
| Energy Forms | Kinetic, Potential, Thermal, Electrical, Chemical, Nuclear. |
| Conservation Laws | Energy, Momentum, and Electric Charge. |
| Waves | Speed (v = f \lambda); amplitude = height, frequency = cycles/second. |
| Electromagnetism | Ohm’s law (V = IR). Magnetic field lines loop around current. |
| Heat & Thermodynamics | 1st Law: ΔU = Q – W. 2nd Law: Entropy increases in isolated systems. |
| Relativity | (E = mc^2); time dilation at relativistic speeds. |
| Quantum Basics | Photons carry energy (E = h\nu). Electrons occupy discrete energy levels. |
3️⃣ Worked Example
Problem:
A 5 kg block is pulled with a horizontal force of 30 N on a frictionless surface. How much acceleration does it experience?
Solution Steps
- Identify the formula – Newton’s Second Law:
[ F = m \times a ] - Plug in values – (F = 30) N, (m = 5) kg.
[ 30 = 5 \times a ] - Solve for (a) –
[ a = \frac{30}{5} = 6 \text{ m/s}^2 ] - Answer – The block accelerates at 6 m/s².
Quick tip: Remember to keep units consistent (kg for mass, N for force, m/s² for acceleration).
4️⃣ Quick Revision Summary
| Topic | Core Idea | Remember |
|---|---|---|
| SI Units | Base units for measurement | 1 m, 1 kg, 1 s, etc. |
| Newton’s Laws | Motion & forces | (F = ma), action‑reaction |
| Energy | Forms & conservation | KE + PE = constant (no friction) |
| Waves | Speed, frequency, amplitude | (v = f\lambda) |
| Electricity | Current, voltage, resistance | Ohm’s law |
| Thermal | Heat, temperature, entropy | 1st & 2nd laws |
| Modern Physics | Relativity & quantum | (E=mc^2), photon energy |
📌 Final Tips
- Conceptual clarity – Focus on why things happen, not just formulas.
- Use diagrams – Sketch simple force diagrams, wave graphs, and electric circuit sketches.
- Practice quick calculations – For TET, you only need to perform basic algebraic manipulations.
- Stay updated – Read recent news on physics discoveries (e.g., gravitational waves, quantum computing) for the Current Affairs section.
Good luck with your TET preparation! 🚀