OpenStax University Physics/E&M

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Each link below leads two different variations of equation sheets used in the electromagnetism unit OpenStax University Physics (Volume 2 Unit 2).

Chapter 5[edit | edit source]

8.85×10−12 F/m = vacuum permittivity.

e = 1.602×10−19C: negative (positive) charge for electrons (protons)

= 8.99×109 m/F



= field above an infinite plane of charge.

Chapter 6[edit | edit source]

= electric flux


Chapter 7[edit | edit source]

= electric potential

= change in potential energy (or simply )

Electron (proton) mass = 9.11×10−31kg (1.67× 10−27kg). Elementary charge = e = 1.602×10−19C.

=kinetic energy. 1 eV = 1.602×10−19J

near isolated point charge

Many charges: .

Chapter 8[edit | edit source]

defines capacitance.

where A is area and d<<A1/2 is gap length of parallel plate capacitor


= stored energy

= energy density

Chapter 9[edit | edit source]

Electric current: 1 Amp (A) = 1 Coulomb (C) per second (s)

Current=, where

= (density, charge, speed, Area)

where =current density.

= electric field where = resistivity

, and ,

where is resistance

and Power=

Chapter 10[edit | edit source]

where =internal resistance and =emf.


Kirchhoff Junction: and Loop:

Charging an RC (resistor-capacitor) circuit: and where is RC time, and .

Discharging an RC circuit: and

Chapter 11[edit | edit source]

cross product

, ,
Magnetic force: .
=EXB drift velocity
Circular motion (uniform B field): Period=

Hall effect

Dipole moment=. Torque=. Stored energy=.
Hall field =
Lorentz force =

Chapter 12[edit | edit source]

Free space permeability T·m/A
Force between parallel wires
Biot–Savart law
Ampère's Law:
Magnetic field inside solenoid with paramagnetic material = where = permeability

Chapter 13[edit | edit source]

Magnetic flux
Motional if
Electromotive "force" (volts)
rotating coil

Chapter 14[edit | edit source]

Unit of inductance = Henry (H)=1V·s/A

Mutual inductance: where =flux through 1 due to current in 2. Reciprocity


, , Stored energy=

in LR circuit where .

in LC circuit where

Chapter 15[edit | edit source]

AC voltage and current if
RMS values and
Resistor where
Capacitor where
Inductor where
RLC series circuit where and
Resonant angular frequency
Quality factor
Average power
Transformer voltages and currents

Chapter 16[edit | edit source]

Displacement current where is the electric flux.

Maxwell's equations:


Poynting vector =energy flux

Average intensity

Radiation pressure (perfect absorber) and (perfect reflector).

Index[edit | edit source]

(Vol. 2):    5:Electric Charges and Fields    6:Gauss's Law    7:Electric Potential    8:Capacitance    9:Current and Resistance    10:Direct-Current Circuits    11:Magnetic Forces and Fields    12:Sources of Magnetic Fields    13:Electromagnetic Induction    14:Inductance    15:Alternating-Current Circuits    16:Electromagnetic Waves


  1. transclusions between OpenStax_University_Physics/E&M#Index and Quizbank/Electricity and Magnetism (calculus based)/Equations