PHY102 General Physics II - Electrostatics, Circuits & Magnetism Flashcards

Vocabulary practice flashcards defining core terms, laws, principles, and concepts from the PHY102 General Physics II study notes.

Electrostatics

The study of stationary (or slowly-moving) electric charges and the forces they exert on each other.

Electric Charge

A fundamental property of matter that determines how particles respond to electric and magnetic fields.

Elementary Charge ($e$)

The smallest unit of charge in nature, equal to $1.602 \times 10^{-19},\text{C}$.

Conductor

A material in which electrons are free to move easily, such as copper, aluminum, or gold.

Insulator

A material in which electrons are bound tightly to atoms and cannot move freely, such as rubber, plastic, or glass.

Friction (Triboelectric Charging)

A method of charging where rubbing two dissimilar insulators together transfers electrons from one material to the other.

Conduction (Contact Charging)

A method of charging where a charged conductor touches an uncharged conductor, redistributing charge between them.

Induction (Electrostatic Induction)

A method where a charged object induces an opposite charge on a nearby uncharged conductor without making physical contact.

Coulomb's Law

States that the electrostatic force between two point charges is directly proportional to the product of their magnitudes and inversely proportional to the square of the distance between them: $F = k \frac{|q_1 \times q_2|}{r^2}$.

Principle of Superposition

States that the total force or electric field acting on a charge is the vector sum of the individual forces or electric fields exerted by all other charges present.

Electric Field ($E$)

The force per unit charge experienced by a small positive test charge placed at a given point in space, defined as $E = \frac{F}{q_{\text{test}}}$.

Electric Field Lines

Imaginary curves that originate from positive charges and terminate on negative charges, used to visualize the direction and strength of an electric field.

Electric Flux (\text{\textPhi}_E)

A measure of the number of electric field lines passing through a given surface, defined as \text{\textPhi}_E = E A \text{cos}(\text{\texttheta}).

Gauss's Law

States that the total electric flux through any closed Gaussian surface equals the net enclosed electric charge divided by the permittivity of free space: \text{\textoint} E \text{\textperiodcentered} dA = \frac{Q_{\text{enclosed}}}{\text{\textepsilon}_0}.

Permittivity of Free Space (\text{\textepsilon}_0)

A physical constant representing the capability of a vacuum to permit electric field lines, equal to 8.854 \times 10^{-12},\text{C}^2/(\text{N} \text{\textperiodcentered} \text{m}^2).

Electric Potential ($V$)

The work per unit charge needed to move a test charge from infinity to a specific point in an electric field, given by $V = \frac{W}{q}$ and measured in Volts ($\text{V}$).

Electric Potential Energy ($U$)

The work required to bring a charge from infinity to a given point against an electric field, given by $U = q V$.

Dielectric

An insulating material that becomes electrically polarized when placed in an external electric field.

Dielectric Constant (\text{\textkappa})

The ratio of the applied electric field in vacuum to the reduced electric field inside a dielectric material: \text{\textkappa} = \frac{E_0}{E_{\text{inside}}}.

Capacitance ($C$)

The ratio of stored electric charge magnitude to the potential difference across a capacitor, defined as $C = \frac{Q}{V}$ and measured in Farads ($\text{F}$).

Electric Dipole

A system consisting of two equal and opposite charges separated by a small distance $d$.

Electric Dipole Moment ($p$)

A vector quantity measuring the strength of an electric dipole, equal to the charge magnitude times separation distance: $p = q d$.

Electric Current ($I$)

The rate at which electric charge flows past a given cross-section of a conductor, defined as $I = \frac{Q}{t}$ and measured in Amperes ($\text{A}$).

Electromotive Force (\text{\textmathcal{E}})

The energy per unit charge supplied by a source (such as a battery) to move charge through a complete circuit.

Resistance ($R$)

The opposition to the flow of electric current, defined by Ohm's Law as $R = \frac{V}{I}$ and measured in Ohms (\text{\textOmega}).

Resistivity (\text{\textrho})

An intrinsic property of a material that quantifies how strongly it opposes current flow, related to resistance by R = \text{\textrho} \frac{L}{A}.

Kirchhoff's Current Law (KCL)

States that at any circuit junction, the total current flowing into the junction equals the total current flowing out: \text{\textsum} I_{\text{in}} = \text{\textsum} I_{\text{out}}.

Kirchhoff's Voltage Law (KVL)

States that the algebraic sum of all potential differences around any closed circuit loop is zero: \text{\textsum} V = 0.

Maximum Power Transfer Theorem

States that a load receives maximum electrical power from a source when the load resistance equals the internal resistance of the source ($R_{\text{load}} = r_{\text{source}}$).

Magnetic Field ($B$)

A vector field that exerts a magnetic force on moving electric charges and magnetic dipoles, measured in Tesla ($\text{T}$).

Lorentz Force

The force exerted on a charge $q$ moving with velocity $v$ through a magnetic field $B$, given by $F = q(v \times B)$ with magnitude F = q v B \text{sin}(\text{\texttheta}).

Magnetic Flux (\text{\textPhi}_B)

A measure of the total magnetic field passing through a surface area, given by \text{\textPhi}_B = B A \text{cos}(\text{\texttheta}) and measured in Webers ($\text{Wb}$).