Explore the Universe Through Physics

Visualizing the fundamental concepts that govern our reality

Branches of Physics

Mechanics

The branch of physics related to the laws of motions and gravitation.

Newton's Laws Gravity

Thermodynamics

The study of heat and temperature and their relationship with energy and work.

Heat Transfer Entropy

Nuclear Physics

The study of the nucleus of an atom and nuclear reactions.

Fission Fusion

Physical Quantities

Fundamental Quantities

Physical quantities which cannot be explained by other physical quantities.

Examples:

  • Time (s)
  • Length (m)
  • Mass (kg)

Derived Quantities

Physical quantities which are explained on the basis of fundamental quantities.

Examples:

  • Velocity (m/s)
  • Area (m²)
  • Acceleration (m/s²)

Density

Mass per unit volume is called density. It is a scalar quantity.

Formula:

ρ = m / v

where ρ is density, m is mass, and v is volume

Units:

kg/m³ g/cm³

Volume Formulas:

Cylinder:

V = πr²h

Sphere:

V = (4/3)πr³

Measuring Instruments

Vernier Caliper

A precision instrument used to measure dimensions with high accuracy.

Least Count: 0.01 cm
Main Scale: cm and mm

Screw Gauge

Measures small lengths or diameters with high precision.

Least Count: 0.001 cm
Pitch: 1 mm

Stopwatch

Measures time intervals between two events with precision.

Type: Digital/Mechanical
Least Count: 0.01 s

Instrument Precision Comparison