Entropy
A measure of the disorder or randomness in a system.
Carnot Engine Efficiency
Efficiency equals 1 minus cold reservoir temperature over hot reservoir temperature (e=1-Tc/Th).
Energy Stored in a Capacitor
Energy equals one half capacitance times voltage squared (U=1/2CV^2).
Boyle's Law
For a fixed amount of gas at constant temperature, pressure inversely proportional to volume (P1V1=P2V2).
Archimedes' Principle
The upward buoyant force on an object immersed in fluid is equal to the weight of the fluid displaced.
Electric Potential Energy
Electric potential energy equals charge times electric potential (U=qV).
Conservation of Mechanical Energy
In a closed system, the sum of kinetic and potential energy remains constant.
Conservation of Momentum
In a closed system, total momentum before equals total momentum after an event.
De Broglie Wavelength
A particle's wavelength is inversely proportional to its momentum (λ=h/p).
Avogadro's Law
Equal volumes of gases at the same temperature and pressure contain equal numbers of molecules.
Charles's Law
For a fixed amount of gas at constant pressure, volume directly proportional to temperature (V1/T1=V2/T2).
Brewster's Angle
The angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection.
Coulomb's Law
Electrostatic force equals k times charge1 times charge2 divided by distance squared (Fe=k(q1q2)/r^2).
Compton Scattering
The increase in wavelength (and decrease in energy) of X-rays or gamma rays when scattered.
Critical Angle
The angle of incidence above which total internal reflection occurs.
Conservation of Angular Momentum
Angular momentum remains constant if no external torques act on the system.
Capacitance Formula
Capacitance equals charge divided by voltage (C=Q/V).
Biot-Savart Law
Calculates magnetic field produced by a current-carrying wire.
Doppler Effect
Change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source.
Coulomb’s Law (Electric Fields)
Electric force between charged objects depends on the distance between the objects and the magnitude of the charges.
Continuity Equation for Fluids
Area times velocity remains constant (A1v1=A2v2).
Angular Momentum
Angular momentum equals moment of inertia times angular velocity (L=Iω).
Ampere’s Law
The magnetic field in space around an electric current is proportional to the electric current.
Bernoulli’s Equation
Pressure plus one half density times velocity squared plus density times gravity times height is constant.
Black Body Radiation
The electromagnetic radiation emitted by a body in thermal equilibrium.