List of Basic Physics Relations - Class 11 and Class 12
FAQs on Physics Theories - Branches and Laws with Respective Fields
1. What are the major branches of Physics?
Physics is broadly divided into two main types: Classical Physics and Modern Physics. Each has several specialised branches:
- Classical Physics: This deals with macroscopic phenomena and includes branches like Mechanics, Acoustics (sound), Optics (light), Thermodynamics (heat), and Electromagnetism.
- Modern Physics: This focuses on microscopic and high-velocity phenomena, covering branches such as Atomic Physics, Nuclear Physics, Quantum Mechanics, and Relativity.
2. What are the five great theories that form the foundation of Physics?
The core of our understanding of the physical world can be summarised by five fundamental theories:
- Classical Mechanics: Describes the motion of objects, governed by Newton's Laws.
- Electromagnetism: Unifies electricity, magnetism, and light into a single framework described by Maxwell's Equations.
- Thermodynamics: Explains heat, energy, and the behaviour of large systems of particles.
- Special & General Relativity: Einstein's theory describing gravity and the relationship between space, time, and motion at high speeds.
- Quantum Mechanics: Describes the behaviour of matter and energy at the atomic and subatomic levels.
3. How does Classical Physics differ from Modern Physics?
The primary difference between Classical Physics and Modern Physics lies in the scale and speed of the systems they describe. Classical Physics, based on the work of Newton, applies to large-scale (macroscopic) objects moving at speeds much slower than light. Modern Physics, emerging from the work of Einstein and Planck, is required to explain phenomena at the atomic and subatomic (microscopic) level or for objects moving at speeds close to the speed of light.
4. Why is understanding the branches and laws of Physics important for students?
Understanding the various branches and fundamental laws is crucial as it provides a structured framework for the entire subject. It helps students connect different concepts across the CBSE Class 11 and 12 syllabus, moving from basic principles to complex applications. This foundational knowledge is essential for understanding how the universe works, from everyday phenomena like electricity and motion to advanced topics in engineering and technology.
5. What are some of the fundamental laws of Physics every student should know?
Several laws form the bedrock of physics concepts taught in schools. Key examples include:
- Newton's Laws of Motion: Define the relationship between an object's motion and the forces acting upon it.
- Law of Universal Gravitation: Describes the gravitational attraction between two masses.
- The Laws of Thermodynamics: Govern energy, heat, and work.
- Ohm's Law: Defines the relationship between voltage, current, and resistance in an electrical circuit.
6. How do theoretical and experimental physics work together to advance scientific knowledge?
Theoretical and experimental physics have a synergistic relationship that drives scientific progress. Theoretical physicists use mathematics to create models and hypotheses to explain observations and predict new phenomena. Experimental physicists then design and conduct experiments to test these predictions. The results either confirm the theory or reveal unexpected outcomes, which in turn prompts theorists to refine existing models or develop entirely new ones, creating a continuous cycle of discovery.
7. What is the difference between a law and a theory in Physics?
In Physics, a law is a concise statement, often a mathematical equation, that describes a specific natural phenomenon observed to be universally true under certain conditions (e.g., Newton's Law of Universal Gravitation). A theory, on the other hand, is a comprehensive and well-substantiated explanation for a broad range of phenomena, supported by a vast body of evidence from experiments. For example, Einstein's Theory of Relativity explains the law of gravity.
