Introduction to Physics: Classical vs Modern

Study Notes

Overview of Physics

Physics studies the interaction of matter, force, and energy.
Divided into classical physics (pre-1900) and modern physics (post-1900).

Classical Physics

Major branches include:
- Mechanics: Focuses on motion, force, work, energy, and fluids.
- Heat and Thermodynamics: Deals with heat effects, transfer methods, and conversion of heat energy to mechanical work.
- Optics: Studies light and its properties.
- Electricity and Magnetism: Examines electrical charges and their interactions with magnetism.
- Wave Motion and Sound: Investigates characteristics and behavior of waves.
Classical physics generally addresses macroscopic phenomena at low velocities relative to light.
Speed of light in vacuum is approximately 3 x 10^8 m/s.

Modern Physics

Emerged in 1900 starting with Max Planck's work on blackbody radiation.
Major areas include:
- Nuclear Physics: Studies atomic nucleus properties and reactions.
- General Relativity: Explains how matter bends space-time, influencing the paths of matter and light.
- Special Relativity: Covers high-speed phenomena near light's speed.
- Particle Physics: Focuses on elementary particles, the building blocks of matter.
- Quantum Mechanics: Explores matter and energy behavior at atomic and subatomic scales.

Measurement in Physics

Physics involves experiments to test hypotheses or theories, requiring precise measurements.
Measurement compares a quantity to a standard.
Established systems of units include:
- Metric System: Includes mks (meter, kilogram, second) and egs (centimeter, gram, second).
- English System (FPS): Represents foot, pound, second; recognizes pound-force as a fundamental quantity.

International System of Units (SI)

SI is the modern metric system, legally enforced worldwide.
Consists of fundamental and derived physical quantities:
- Fundamental Quantities: Independent basic properties (length, mass, time, temperature, electric current, luminous intensity, amount of substance).
- Derived Quantities: Based on fundamental quantities (e.g., speed = length/time; also includes acceleration, density, work, energy).

SI Fundamental Units

Defined as follows:
- Meter (m) for length
- Kilogram (kg) for mass
- Second (s) for time
- Kelvin (K) for temperature
- Ampere (A) for electric current
- Candela (cd) for luminous intensity
- Mole (mol) for amount of substance
Derived units are formed by combining these fundamental units.

Description

This quiz explores the fundamentals of physics, distinguishing between classical and modern physics. It covers key principles, discoveries, and the evolution of the subject from 1900 onwards. Test your understanding of mechanics, thermodynamics, optics, and more!