Physics Definitions Start from C

Chromospheres - The layer of the solar atmosphere that is located above the photosphere and beneath the transition region and the corona. The chromospheres is hotter than the photosphere but not as hot as the corona.

Circular Accelerator - A type physics research machine that brings moving particles into collision with one another for the purpose of studying the outcome. As opposed to a fixed-target machine, which smashes moving particles into a stationary object.

Collider - Radiation that is emitted when a free electron is deflected by an ion, but the free electron is not captured by the ion. Generally, it is a type of radiation emitted when high energy electrons are accelerated. (German for braking radiation)

Color - The basic characteristic that differentiates the six varieties of quark.

Contour Map - A map showing the intensity of radiation as a function of position. Each contour line corresponds to a specific intensity of radiation, with inner contours corresponding to higher intensities than outer contours. Therefore, a closed contour encircles a region where the intensity of the emitted radiation is greater than or equal to the intensity on the contour line. The contours outline the shape of the emitting source.

Convection - The physical upwelling of hot matter, thus transporting energy from a lower, hotter region to a higher, cooler region. A bubble of gas that is hotter than its surroundings expands and rises. When it has cooled by passing on its extra heat to its surroundings, the bubble sinks again. Convection can occur when there is a substantial decrease in temperature with height, such as in the Sun's convection zone.

Convection Zone - A layer in a star in which convection currents are the main mechanism by which energy is transported outward. In the Sun, a convection zone extends from just below the photosphere to about seventy percent of the solar radius.

Corona - The outermost layer of the solar atmosphere. The corona consists of a highly rarefied gas with a low density and a temperature greater than one million degrees Kelvin. It is visible to the naked eye during a solar eclipse.

Calorimeter - Device that isolates objects to measure temperature changes do to heat flow.

Candela - Unit of luminous intensity.

Capacitance - Ratio of charge stored per increase in potential difference.

Capacitor - Electrical device used to store charge and energy in the electrical field.

Capillary Action - Rise of liquid in narrow tube due to surface tension.

Carnot Efficiency - Ideal efficiency of heat engine or refrigerator working between two constant temperatures.

Centripetal Force - Force that causes centripetal acceleration.

Chain Reaction - Nuclear reaction in which neutrons are produced that can cause further reactions.

Charged - Object that has an unbalance of positive and negative electrical charges.

Charging by Conduction - Process of charging by touching neutral object to a charged object.

Charging by Induction - Process of charging by bringing neutral object near charged object, then removing part of resulting separated charge.

Chromatic Aberration - Variation in focal length of lens with wavelength of light.

Circular Motion - Motion with constant radius of curvature caused by acceleration being perpendicular to velocity.

Clock Reading - Time between event and a reference time, usually zero.

Closed, Isolated System - Collection of objects such that neither matter nor energy can enter or leave the collection.

Closed-pipe Resonator - Cylindrical tube with one end closed and a sound source at other end.

Coefficient of Friction - Ratio of frictional force and the normal force between two forces.

Coefficient of Linear Expansion - Change in length divided by original length and by temperature change.

Coefficient of Volume Expansion - Change in volume divided by original volume and by temperature change.

Coherent Waves - Waves in which all are in step; are in phase.

Cohesive Force - Attractive force between similar substances.

Complementary Color - Two colors that, when added , produce white light. Two pigments, that when combined, produce black.

Compound Machine - Machine consisting of two or more simple machines.

Compton Effect - Interaction of photons, usually X rays, with electrons in matter resulting in increased wavelength of X rays and kinetic energy of electrons.

Concave Lens - Lens thinner in center than edges; a diverging lens.

Concave Mirror - Converging mirror, one with center of curvature on reflecting side of mirror.

Conduction Band - Energies of charge carries in a solid such that the carries are free to move.

Conductor - Materials through which charged particles move readily; or heat flow readily.

Conserved Properties - Property that is the same before and after an interaction.

Consonance - Two or more sounds that, when heard together, sound pleasant.

Constant Acceleration - Acceleration that does not change in time.

Constant Velocity - Velocity that does not change in time.

Constructive Interference - Superposition of waves resulting in a combined wave with amplitude larger than the component waves.

Conventional Current - Motion of positive electrical current.

Converging Lens - Lens that causes light rays to converge; usually a convex lens.

Convex Lens - Lens that is thicker in the center than at edges.

Convex Mirror: Diverging mirror - Center of curvature is on side opposite reflecting side of mirror.

Cosine - The ratio of the adjacent side to the hypotenuse.

Coulomb - Unit of electrical charge. Charge caused by flow of one ampere for one second.

Crest of Wave - High point of wave motion.

Critical Angle - Minimum angle of incidence that produces total internal reflection.

Crystal Lattice - Structure of solid consisting of regular arrangement of atoms.