Branches of Applied Physics

Applied Physics

• Applied physics focuses on practical applications of physical principles and theories to solve real-world problems and develop technologies.
• It bridges the gap between pure physics and engineering by emphasizing experimental techniques and the development of new materials, devices, and systems.

Branches of Applied Physics

• Mechanics: Studies forces and motion, influencing engineering, robotics, aerospace, and other fields.
• Condensed Matter Physics: Investigates properties of solids and liquids, impacting materials science, nanotechnology, and semiconductor physics.
• Optics: Studies light and its interactions with matter, leading to applications in lenses, lasers, and imaging technologies.
• Thermal Physics: Focuses on heat transfer, thermodynamics, and statistical mechanics, impacting engineering fields like HVAC and energy systems.
• Acoustics: Studies sound and its propagation, leading to applications in audio technology, noise control, and architectural design.
• Medical Physics: Applies physics concepts to medicine, including the development of imaging technologies (like MRI and X-ray) and radiation therapy for cancer treatment.
• Computational Physics: Employs numerical methods and simulations to solve complex physical problems, widely applied in research and engineering.
• Plasma Physics: Studies ionized gases and their applications in nuclear fusion, space physics, and technologies like plasma displays.
• Biophysics: Combines physics and biology to understand biological systems, contributing to medical technologies and biomaterials.
• Nanotechnology: Focuses on manipulating matter at the nanoscale, impacting materials science, electronics, and drug delivery systems.

Theory of Mechanics

• Theory of Machines is a branch of engineering-science that studies the relative motion between components of a machine and the forces acting on them.

Branches of Mechanics

• By type of body:
  • Rigid Body Mechanics: Deals with bodies that do not deform under applied forces.
  • Deformable Body Mechanics: Studies bodies that deform under applied forces.
  • Fluid Mechanics: Focuses on the behavior of fluids (liquids and gases).
• By motion of body:
  • Statics: Deals with forces and their effects on bodies at rest.
  • Dynamics: Deals with forces and their effects on bodies in motion.
    • Kinematics: Studies the motion of objects without considering the forces causing the motion.
    • Kinetics: Focuses on the forces that cause motion and the relationships between motion and forces.

Units

• Units in physics are standard measures for quantities.
• Fundamental Units: Internationally accepted units for fundamental physical quantities (e.g., meter, kilogram, second). Also known as SI Units.
• Derived Units: Units derived from fundamental units (e.g., area, speed, volume).

System of Units

• A system of units is a set of related units used for calculations. It includes base units (representing base dimensions) and derived units (representing products of powers of base dimensions).
• Classification:
  • C.G.S System: Centimeter, gram, second. Known as absolute units.
  • F.P.S System: Foot, pound, second.
  • M.K.S System: Meter, kilogram, second. Known as gravitational units.
  • S.I System: International System of Units.

S.I System of Units

• It uses prefixes to represent convenient units for very small or large measurements.
• Prefix List:
  • Yotta (Y): 10^24
  • Zetta (Z): 10^21
  • Exa (E): 10^18
  • Peta (P): 10^15
  • Tera (T): 10^12
  • Giga (G): 10^9
  • Mega (M): 10^6
  • Kilo (k): 10^3
  • Hecto (h): 10^2
  • Deka (da): 10^1
  • Deci (d): 10^-1
  • Centi (c): 10^-2
  • Milli (m): 10^-3
  • Micro (µ): 10^-6
  • Nano (n): 10^-9
  • Pico (p): 10^-12
  • Femto (f): 10^-15
  • Atto (a): 10^-18
  • Zepto (z): 10^-21
  • Yocto (y): 10^-24

Rules of SI Units

• A dash separates units that multiply each other (e.g., N-m for newton meter).
• Plurals are not used in symbols (e.g., m for meter).
• All units are written in lowercase letters unless they start with a scientist's name (e.g., N for newton, W for watt).
• Units starting with a scientist's name are not capitalized when using the full form.