أكاديميا - كولنز - معاجم الجيب العلمية - الفيزياء - انكليزي - فرنسي - عربي الحرف ١_ c

Academia - Collins - Pocket Scientific Dictionaries - Physics - English - French - Arabic Letter 1_ C


cable ratings
puissance f des câbles

Cable capacity. Electrical wires or cables must be thick enough to allow the current for which they are designed to pass through them without causing them to heat up. Power is given as a measurement of the maximum current (usually 240) volts that can be used safely. The usual values ​​range between 3 amps (for lighting) and 68 amps (for cooking). See three pin plug.


calibration
calibration f

Calibration. This is the stage in which the scale is set when making any device to measure a quantity. Calibration involves using the device under precisely defined conditions, or checking it against a specific standard.


Calorie
Calorie f

Calorie. The unit of energy content of food, and the kilojoule has begun to replace it, as one calorie equals 4.2 kilojoules. A small calorie equals 4.2 joules.


camera
camera f

Photographer. camera . An optical instrument provides a permanent record of a scene. The film absorbs direct light coming from the scene, causing chemical changes that depend on the brightness and color of the light absorbed in each spot. Developing the film makes the chemical changes permanent.

* Adjust the distance between the lens (A) and the film (D) so that the image is in sharp focus.

* The iris diaphragm (B) is placed at an opening that allows the correct amount of light to pass through.

* The shutter (c) opens and allows the light to fall on the film for an appropriate period of time.

* All of these parts are contained within a light-tight box, or “body,” pictured (e).


camera, pin-hole
stenoscope m

Pinhole camera. A camera without a lens. If the function of the lens is to produce a clear image, then the use of a very small aperture is possible in its absence. Otherwise, the image is unclear, and the small hole passes little light. Therefore, the film of the pinhole camera must be exposed to light for a long period of time, which makes the use of this tool limited to photographing static objects.


capacitor
capacité f

Capacities. Condenser. A device capable of storing charge and energy. It essentially consists of an insulator sandwiched between two metal plates. Applying a voltage of 7 leads to the accumulation of charge on the two plates, as in diagram (a). The current 1 decreases, as in diagram (b), and reaches zero when the voltage between the two plates becomes equal to the applied voltage (c).

The capacitor then becomes a carrier of charge Q, represented by the equation Q = CV, where C is the capacitance, the capacitance or stored charge when the voltage equals 17. The unit used is the farad.

C depends on the area of ​​overlap of the two plates, the distance between them, and the material between them (dielectric). Variable capacitors work by changing the surface area.

Although the primary use of a capacitor is to store charge, as in smoothing (see rectifier), the device is of great importance in many types of circuits, such as time delay circuits.


capillarity
Capillarité f

Poetics. Surface tension effect. Most liquids tend to rise inside a narrow tube (a), although mercury falls in such a tube because the crescent surface curves downward (b). See also. adhesion.

A capillary tube has a narrow lumen.