Physics Basics – Study Notes for LIC/GIC General Awareness & Current Affairs
(Prepared by an expert teacher – concise, clear, and exam‑ready)
1. Simple Explanation
Physics is the branch of science that studies the fundamental laws governing matter, energy, space, and time.
In the context of competitive exams like LIC/GIC, a basic grasp of physics helps you:
- Understand everyday phenomena (e.g., why cars accelerate, why light bends).
- Answer questions about technology, engineering, and science news.
- Show logical reasoning in quantitative sections (e.g., simple math‑physics problems).
2. Key Points (Core Topics)
| Area | Main Concepts | Key Formulas / Laws |
|---|---|---|
| Classical Mechanics | Motion, forces, work, energy | • ( F = ma ) (Newton’s 2nd law) • ( W = F \cdot d \cos\theta ) • ( KE = \tfrac{1}{2}mv^2 ) • ( PE = mgh ) |
| Kinematics | Velocity, acceleration, time | • ( v = u + at ) • ( s = ut + \tfrac{1}{2}at^2 ) |
| Thermodynamics | Heat, temperature, energy transfer | • ( Q = mc\Delta T ) • 1st Law: ( \Delta U = Q - W ) |
| Electricity & Magnetism | Current, voltage, resistance, magnetic fields | • Ohm’s Law: ( V = IR ) • ( \mathbf{F} = q(\mathbf{E} + \mathbf{v} \times \mathbf{B}) ) |
| Waves & Optics | Reflection, refraction, interference | • Snell’s Law: ( n_1\sin\theta_1 = n_2\sin\theta_2 ) • ( c = f\lambda ) |
| Modern Physics | Relativity, quantum, atomic structure | • ( E = mc^2 ) (Relativity) • ( E = h\nu ) (Photons) |
| Astronomy & Space | Planetary motion, black holes, satellites | • Kepler’s laws, orbital velocity ( v = \sqrt{\frac{GM}{r}} ) |
3. Worked Example
Problem (Typical of LIC/GIC Quantitative Section)
*A car starts from rest and accelerates uniformly to a speed of 20 m/s in 10 s.
- What is its acceleration?
- What distance does it cover in that time?*
Solution
-
Acceleration
[ a = \frac{v - u}{t} = \frac{20\text{ m/s} - 0}{10\text{ s}} = 2\text{ m/s}^2 ] -
Distance
[ s = ut + \frac{1}{2}at^2 = 0 + \frac{1}{2}(2)(10)^2 = 100\text{ m} ]
Answer
- Acceleration = 2 m/s²
- Distance covered = 100 m
4. Quick Revision Summary
| Concept | Formula | Quick Tip |
|---|---|---|
| Force & Motion | ( F = ma ) | Force is mass × acceleration. |
| Speed/Velocity | ( v = \frac{s}{t} ) | Average speed vs. instantaneous. |
| Acceleration | ( a = \frac{v-u}{t} ) | Positive = speeding up. |
| Work | ( W = F \cdot s \cos\theta ) | Work only when force has a component along the displacement. |
| Kinetic Energy | ( KE = \tfrac{1}{2}mv^2 ) | Energy due to motion. |
| Potential Energy (gravity) | ( PE = mgh ) | Height * gravity * mass. |
| Heat Capacity | ( Q = mc\Delta T ) | Heat needed = mass × specific heat × temperature change. |
| Ohm’s Law | ( V = IR ) | Voltage = current × resistance. |
| Snell’s Law | ( n_1\sin\theta_1 = n_2\sin\theta_2 ) | Describes refraction. |
| Energy–Mass Relation | ( E = mc^2 ) | Mass can be converted to energy. |
| Photon Energy | ( E = h\nu ) | ( h ) = Planck constant, ( \nu ) = frequency. |
Final Tips for Exam
- Memorize the key formulas – write them on a small note card.
- Practice quick calculations – use the worked example as a template.
- Connect to current affairs – e.g., latest space missions, renewable energy tech (solar panels rely on photon energy), electric vehicles (Ohm’s law, battery capacity).
- Read news articles – many cover physics topics (e.g., “new high‑efficiency LED technology” or “quantum computing breakthroughs”).
Good luck with your preparation!