PHY 1020: Electricity and Magnetism

Comprehensive vocabulary flashcards covering PHY 1020 Chapter 6, including electric charge, fundamental forces, Coulomb's law, circuit properties, AC versus DC power, magnetism, electromagnetic devices, and superconductivity.

Strong Nuclear Force

The fundamental force that holds atomic nuclei together, characterized by a relative strength of $1$, an effective range of $10^{-15}\,\text{m}$, and mediated by gluons and nucleons/pions.

Electromagnetic Force

A fundamental force acting between charged particles with an infinite range and a relative strength of $\frac{1}{137}$, mediated by photons with mass $0$ and spin $1$.

Weak Nuclear Force

A short-range fundamental force with a range of $10^{-18}\,\text{m}$ and a relative strength of $10^{-6}$ that mediates neutrino interactions, induces beta decay, and is carried by intermediate vector bosons ($W^+$, $W^-$, and $Z^0$).

Gravitational Force

The weakest fundamental force, having an infinite range and a relative strength of $6 \times 10^{-39}$, which acts attractively between all masses and is hypothetically mediated by gravitons.

Electric Charge

A fundamental, conserved property of matter that exists in two varieties, positive and negative, which cannot be broken down any further.

Fundamental Quantized Charge ($e$)

The discrete minimum unit of electric charge carried by a single electron or proton, having a magnitude of $1.6 \times 10^{-19}\,\text{C}$.

Coulomb's Law

A physical law stating that the electrostatic force between two point charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them: $F = \frac{k q_1 q_2}{r^2} = \frac{q_1 q_2}{4\pi \varepsilon_0 r^2}$.

Permittivity of Free Space ($\varepsilon_0$)

A fundamental physical constant describing the capability of an electric field to permeate a vacuum, with an exact value given as $8.854 \times 10^{-12}\,\text{F/m}$.

Electric Potential (Voltage)

The electrical push produced by a charge that possesses the capacity to do work on other charges, analogous to a hill enabling an object to roll down.

Electric Current ($I$)

The rate of flow of electric charge through a conductor over time, measured in coulombs per second or amperes ($\text{A}$).

Electrical Resistance ($R$)

The opposition that a material presents to the free movement of electrons, quantified in ohms ($\Omega$) and related to voltage and current by $R = \frac{V}{I}$.

Static Electricity

The accumulation of stationary electric charge on a body resulting from the loss (yielding a positive charge) or gain (yielding a negative charge) of electrons.

Electric Power ($P$)

The rate at which electrical energy is delivered or transformed in a circuit, defined by the formula $P = V I$.

Direct Current (DC)

An electric current that flows unidirectionally through a circuit with a constant magnitude and a frequency of $0\,\text{Hz}$.

Alternating Current (AC)

An electric current that periodically reverses its flow direction, varying in magnitude over time at a frequency of $50\,\text{Hz}$ or $60\,\text{Hz}$.

The War of the Currents

The historic technological dispute between Thomas Edison, who championed direct current, and Nikola Tesla, who championed alternating current for long-distance power transmission.

Power Loss in Transmission ($P_{\text{loss}}$)

The energy dissipated as heat when current flows through resistive transmission wires, determined by the formula $P_{\text{loss}} = I^2 R$.

Circuit Breaker

A protective electrical switch designed to interrupt an overloaded circuit when excessive current poses a threat of wire overheating or fire.

Magnetism

A physical phenomenon generated by moving electric charges and intrinsic atomic electron spin, creating magnetic fields with north and south poles.

Magnetic Dipole

A magnetic entity that consists of paired north and south poles that cannot naturally be isolated from one another.

Magnetic Monopole

A theoretical particle possessing an isolated north or south magnetic pole, postulated in certain physical theories but not yet observed naturally.

Ferromagnetism

The permanent magnetism exhibited by materials caused by the macroscopic alignment of individual atomic magnetic dipoles.

Paramagnetism

A form of magnetism whereby materials (such as refrigerator casings) only exhibit magnetic behavior while in the presence of an external magnetic field.

Curie Temperature

The threshold temperature at which thermal agitation destroys the magnetic ordering of a permanent magnet.

Rare Earth Magnets

High-strength permanent magnets fabricated from elements with high electron populations in their outer shells, giving them exceptionally strong magnetic fields.

Electromagnet

A magnet whose magnetic field is generated by passing an electric current through a coil of wire.

Transformer

A static electromagnetic device that steps up or steps down alternating voltage and current between circuits according to the turns ratio: $\frac{V_P}{V_S} = \frac{I_S}{I_P} = \frac{N_P}{N_S} = a$.

Commutator

A mechanical rotary switch in a DC motor that reverses the direction of current in the coil every half revolution to maintain continuous torque in one direction.

Dynamo

An electrical generator that converts mechanical energy into direct current (DC).

Alternator

An electrical generator that converts mechanical work into alternating current (AC).

Eddy Currents

Loops of electrical current induced within bulk conductors when moving through or subjected to a changing magnetic field.

Superconductor

A material whose electrical resistance drops entirely to zero when cooled below a characteristic critical transition temperature ($T_c$).

Cooper Pairs

Bound electron pairs with opposite spins that interact with the crystal lattice to travel without resistance through a superconductor.

Meissner Effect

The expulsion of magnetic field lines from the interior of a superconductor as it transitions below its critical temperature, enabling magnetic levitation.