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PhysRef is a free physics formula reference for students: 252 formulas with every symbol defined, 220 built-in calculators that solve them,27 physical constants and a unit converter, across mechanics, waves, electricity, optics and modern physics. No account, on any screen.
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- 252Formulas
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- 27Constants
- 14Unit groups
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Mechanics, heat, waves, fields, optics, relativity, quantum, and nuclear physics.
Mechanics
58 formulas across Kinematics, Dynamics, Work & Energy, and more
Thermodynamics
34 formulas across Heat & Temperature, First Law, Second Law, and more
Waves
37 formulas across Simple Harmonic Motion, Wave Properties, Sound Waves, and more
Electricity & Magnetism
48 formulas across Electrostatics, Electric Circuits, Capacitance, and more
Optics
34 formulas across Reflection, Refraction, Lenses, and more
Modern Physics
41 formulas across Special Relativity, Quantum Mechanics, Atomic Physics, and more
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Unit converter
Convert length, mass, time, pressure, energy, temperature, and more.
Physical constants
Reference universal, electromagnetic, atomic, thermal, and Earth constants.
Study guides
Free guides on memorizing formulas, solving kinematics, avoiding unit errors, and exam prep.
Popular formulas
Start with frequently used equations, then follow related formulas on each detail page.
Velocity is the rate of change of displacement with respect to time.
The net force equals mass times acceleration. Newton's fundamental law.
Energy possessed by an object due to its motion.
Ohm's Law for ohmic conductors.
Describes how light bends when passing between media with different refractive indices.
The most famous equation in physics. Mass and energy are equivalent and interconvertible.