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Showing 181–210 of 1709 reference entries

InformationFinite graphs and trees

Graphs represent pairwise connections; trees impose acyclicity.

Definition
InformationData-structure interfaces and operation costs

An interface defines operations; an implementation determines costs.

Method
InformationLoop invariants and total correctness

An invariant establishes correctness only with its proof obligations.

Method
InformationComparison sorting lower bound

Distinct-key comparisons need enough branches to distinguish orders.

Mathematical statement
InformationBreadth-first and depth-first traversal

Graph searches visit reachable vertices using different orders.

Method
InformationShortest-path algorithm conditions

Edge weights determine which shortest-path method applies.

Method
InformationTuring machines and effective computation

Finite instructions can act on an unbounded writable tape.

Definition
InformationRelations and tabular data

A relation is a set of tuples from declared domains.

Definition
PhysicsCentre-of-mass dynamics

External force controls the mass-weighted centre's acceleration.

Model
PhysicsRigid-body inertia tensor

A tensor relates rotation to angular momentum.

Model
PhysicsEuler equations for a rigid body

Body-axis angular acceleration includes rotation of the axes.

Model
Physics · Mathematics & logicEuler–Lagrange equations

Stationary action supplies coordinate equations of motion.

Mathematical statement
Physics · Mathematics & logicHamilton's canonical equations

Canonical coordinates and momenta evolve from the Hamiltonian.

Mathematical statement
PhysicsFluid mass continuity

Density change balances mass flux through a region.

Model
PhysicsBernoulli's streamline relation

An ideal steady flow balances pressure, motion and height.

Model
PhysicsIncompressible Navier–Stokes equation

Fluid inertia balances pressure, viscosity and gravity.

Model
PhysicsReynolds number

Compare inertial and viscous scales of a flow.

Model
PhysicsDriven damped oscillator

A linear restoring force, damping and periodic drive determine response.

Model
PhysicsIdeal-string wave equation

A local differential equation determines small string disturbances.

Model
Physics · Mathematics & logicWave superposition and interference

Linear disturbances add; their relative phase determines reinforcement.

Model
PhysicsFixed-end string modes

Boundary conditions select standing-wave frequencies.

Model
PhysicsSnell's refraction relation

Angles at an interface depend on refractive indices.

Model
PhysicsThin-lens image equation

A paraxial lens relates object and image distances.

Model
PhysicsSingle-slit diffraction minima

An aperture's finite width selects dark far-field directions.

Model
PhysicsLinear polarization and Malus's law

An ideal analyzer transmits the field component along its axis.

Model
PhysicsElectromagnetic potentials

Scalar and vector potentials encode electric and magnetic fields.

Model
PhysicsCapacitance

A linear two-conductor arrangement stores separated charge.

Definition
PhysicsSelf-inductance

Changing current changes linked magnetic flux and induced emf.

Model
PhysicsElectromagnetic energy balance

The rate of field-energy change balances outward energy flow and power transferred to charges.

Model
PhysicsKirchhoff circuit balances

Lumped circuit models balance node currents and loop voltages.

Model
ModelSource checked

Single-slit diffraction minima

Physics

An aperture's finite width selects dark far-field directions.

Key knowledge

For uniform monochromatic illumination of a single slit, Fraunhofer diffraction minima occur at a sin θ = mλ for nonzero integers m within the allowed angular range.

Values and equations

a sin θ = mλ, m = ±1,±2,…

a
Slit width m
λ
Light wavelength in the propagation medium m
θ
Angle from the forward direction rad
m
Nonzero integer diffraction order

Conditions and scope

  • Far-field approximation, or a lens forming the far-field pattern; slit width a > 0 and normal plane-wave illumination with uniform phase and amplitude across the slit.
  • m = 0 is the central maximum, not a dark fringe; finite near-field patterns need another model.
Sources · 1

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. University Physics 3: Single-Slit DiffractionSamuel J. Ling, Jeff Sanny and William Moebs / OpenStax, Rice UniversityTextbook chapteropenstax.orgRead source

Evidence and review

Section 4.1: paired-wave cancellation and nonzero-order minima.

2026-10-10 · Uniform single-slit far-field minima only; multi-aperture or vector diffraction excluded.

Entry detailsPermanent link to this entry ↗
Record identity
physics-diffraction
Revision
university-reference.1
Structured reference record
University reference · University core expansion