Electricity & Magnetism
Electrostatics, Electric Circuits, Capacitance, Magnetism, Electromagnetic Induction, AC Circuits
Electrostatics
9 formulas
Electric force between two point charges.
Electric field is force per unit charge.
Electric potential energy per unit charge.
Energy stored in configuration of charges.
Electric field between parallel plates.
Electric flux through closed surface equals enclosed charge / ε₀.
Electric dipole moment for two equal and opposite charges.
Electric field along the axis of an electric dipole.
Electric flux through a surface.
Electric Circuits
8 formulas
Ohm's Law for ohmic conductors.
Power dissipated in circuit element.
Current is rate of charge flow.
Resistance of a wire depends on geometry and material.
Total resistance of resistors in series.
Total resistance of resistors in parallel.
Sum of voltage changes around closed loop is zero.
Sum of currents at a node is zero.
Capacitance
8 formulas
Capacitance is charge stored per unit voltage.
Capacitance of parallel plate capacitor.
Energy stored in charged capacitor.
Equivalent capacitance for series connection.
Equivalent capacitance for parallel connection.
Time constant for RC circuit charging/discharging.
Capacitance of parallel plate capacitor with dielectric material.
Energy stored per unit volume in an electric field.
Magnetism
10 formulas
Magnetic force on moving charge (Lorentz force).
Magnetic force on current-carrying wire.
Magnetic field from current element.
Magnetic field around long straight wire.
Uniform magnetic field inside ideal solenoid.
Energy stored per unit volume in a magnetic field.
Frequency of circular motion of charged particle in magnetic field.
Radius of circular motion of charged particle in magnetic field.
Voltage developed across conductor in magnetic field due to Hall effect.
Line integral of magnetic field around closed loop equals μ₀ times enclosed current.
Electromagnetic Induction
8 formulas
Induced EMF equals negative rate of flux change.
Magnetic flux through a surface.
EMF induced in moving conductor.
EMF induced by changing current in same circuit.
Energy stored in magnetic field of inductor.
Time constant for RL circuit current growth or decay.
EMF induced in one coil due to changing current in another.
Voltage ratio in ideal transformer equals turns ratio.
AC Circuits
5 formulas
RMS (root mean square) value of sinusoidal AC voltage or current.
Opposition to AC current flow by a capacitor.
Opposition to AC current flow by an inductor.
Total impedance of series RLC circuit.
Resonant frequency of LC circuit where X_L = X_C.
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