Introduction to Physics

• Physics is a natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.
• Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves.
• Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy.
• Over the last two millennia, physics was a part of natural philosophy, along with chemistry, biology, and certain branches of mathematics, but during the Scientific Revolution in the 16th century, the natural sciences emerged as unique research programs in their own right.
• Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry.
• Physics is related to mathematics, and physical theories are almost always expressed using mathematical formalisms.
• Modern physics is typically divided into classical physics and modern physics.
• Classical physics involves the traditional branches and topics that were recognized and developed prior to the beginning of the 20th century—classical mechanics, thermodynamics, optics, acoustics, and electromagnetism.
• Modern physics involves the more recent branches of physics that developed during the 20th century and beyond—nuclear physics, particle physics, condensed matter physics, and cosmology.

Mechanics

• Mechanics is the study of motion of bodies (objects) and the related concepts of force and energy.
• Mechanics is further divided into:
  • Statics studies bodies at rest
  • Kinematics studies motion without regard to its causes
  • Dynamics studies motion and the forces that cause it

Thermodynamics

• Thermodynamics is the study of heat, work, and the properties of systems in equilibrium.
• Thermodynamics deals with macroscopic variables, such as temperature, internal energy, and entropy.
• Thermodynamics describes how these variables change under different conditions and how they relate to each other.

Optics

• Optics is the study of light and its interactions with matter.
• Optics covers phenomena such as reflection, refraction, diffraction, and interference.
• Optics explores the properties of lenses, mirrors, and other optical devices.

Acoustics

• Acoustics is the study of sound and its properties.
• Acoustics includes the study of sound production, propagation, and reception.
• Acoustics is applied in areas such as musical instrument design and noise control.

Electromagnetism

• Electromagnetism is the study of electric and magnetic forces and fields.
• Electromagnetism includes topics such as electric charge, electric current, electric fields, and magnetic fields.
• Electromagnetism links these phenomena with the concept of electromagnetic radiation, such as light.

Nuclear Physics

• Nuclear physics studies the constituents, structure, behavior, and interactions of atomic nuclei.
• Nuclear physics explores phenomena such as radioactivity, nuclear reactions, and nuclear fission/fusion.
• Nuclear physics is applied in areas such as nuclear power, nuclear medicine, and nuclear weapons.

Particle Physics

• Particle physics studies the fundamental constituents of matter and radiation, and their interactions.
• Particle physics seeks to identify the basic building blocks of the universe and the forces that govern their behavior.
• Particle physics led to the development of the Standard Model, which classifies all known elementary particles and fundamental forces.

Condensed Matter Physics

• Condensed matter physics studies the physical properties of matter in condensed phases.
• Condensed matter physics explores phenomena such as superconductivity, magnetism, and semiconductors.
• Condensed matter physics has applications in materials science and the development of new technologies.

Cosmology

• Cosmology is the study of the origin, evolution, and ultimate fate of the universe.
• Cosmology seeks to understand the large-scale structure of the cosmos, including galaxies, galaxy clusters, and the cosmic microwave background.
• Cosmology relies on theories such as the Big Bang theory and general relativity.