Physics is the study of the fundamental principles that govern the universe. While there are numerous laws, theories, and principles in physics, here are 34 important laws that have had a significant impact on our understanding of the natural world:
34 Important Laws of Physics
- Newton’s First Law (Law of Inertia): An object at rest will stay at rest, and an object in motion will stay in motion unless acted upon by a net external force.
- Newton’s Second Law (F=ma): The force acting on an object is equal to the mass of that object times its acceleration.
- Newton’s Third Law: For every action, there is an equal and opposite reaction.
- Law of Universal Gravitation: Every point mass attracts every other point mass by a force acting along the line intersecting both points.
- First Law of Thermodynamics: Energy cannot be created or destroyed, only transferred or transformed.
- Second Law of Thermodynamics: Entropy of an isolated system always increases over time.
- Third Law of Thermodynamics: The entropy of a system approaches a constant value as its temperature approaches absolute zero.
- Maxwell’s Equations:
- Gauss’s law for electricity.
- Gauss’s law for magnetism.
- Faraday’s law of induction.
- Ampère’s law with Maxwell’s addition.
- Einstein’s Theory of Relativity:
- Special Relativity: Time dilation, length contraction, and the equivalence of mass and energy (E=mc^2).
- General Relativity: Gravity is due to spacetime curvature.
- Planck’s Law: Describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium.
- Heisenberg Uncertainty Principle: It’s impossible to know both the position and momentum of a quantum particle with absolute certainty.
- Schrödinger’s Equation: Describes how the quantum state of a quantum system changes over time.
- Coulomb’s Law: Describes the electrostatic force between charged particles.
- Ohm’s Law: Current through a conductor is proportional to the voltage across it.
- Hooke’s Law: The force needed to extend or compress a spring is proportional to the distance it’s stretched or compressed.
- Archimedes’ Principle: An object submerged in a fluid experiences an upward force equal to the weight of the fluid it displaces.
- Boyle’s Law: For a given amount of gas, pressure is inversely proportional to volume at a constant temperature.
- Charles’ Law: For a given amount of gas, volume is directly proportional to temperature at a constant pressure.
- Lenz’s Law: The direction of the current induced in a circuit always opposes the change in the magnetic field that produced it.
- Kirchhoff’s Laws:
- The sum of currents flowing into a node is equal to the sum flowing out (Junction Rule).
- The sum of voltage drops in a closed loop is zero (Loop Rule).
- Faraday’s Law of Induction: A change in the magnetic field within a loop of wire induces an electromotive force (EMF) in the wire.
- Pauli Exclusion Principle: No two electrons can occupy the same quantum state simultaneously.
- Avogadro’s Law: Equal volumes of all gases, at the same temperature and pressure, have the same number of molecules.
- Bernoulli’s Principle: An increase in the speed of a fluid occurs simultaneously with a decrease in the fluid’s potential energy or pressure.
- Beer-Lambert Law: The absorbance of light is directly proportional to the concentration of the absorbing species in the medium.
- Snell’s Law: The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant for any two particular media.
- Stefan-Boltzmann Law: The total energy radiated by a black body is proportional to the fourth power of its absolute temperature.
- Fick’s First Law: Describes the diffusion of a solute in a solvent.
- Conservation Laws:
- Conservation of Energy.
- Conservation of Momentum.
- Conservation of Angular Momentum.
- Gauss’s Law for Magnetism: The net magnetic flux passing through any closed surface is zero.
- Superposition Principle: In any linear system, the net response is equal to the sum of the individual responses.
- Pascal’s Law: Pressure change at any point in an enclosed fluid is transmitted undiminished to all points in the fluid.
- Laws of Refraction: The incident ray, the refracted ray, and the normal to the interface of two media all lie on the same plane.
