أكاديميا - كولنز - معاجم الجيب العلمية - الفيزياء - انكليزي - فرنسي - عربي الحرف ٤_ s

Academia - Collins - Pocket Scientific Dictionaries - Physics - English - French - Arabic Letter 4_ S


spark
etincelle f

spark. A high-energy discharge through a gas that lasts for a very short period of time. A channel of gas ions carries the current. The large transfer of energy leads to a chemical change, a rise in temperature (producing sound), and electromagnetic waves. See also lightning.


spark counter
Compteur m d'étincelles

Spark counter. A x-ray detector capable of detecting alpha particles. Sparks are emitted across a gap of 5 kV when ions pass through from an alpha source.

Particle path
Sparks
High voltage


specific
specific

qualitative. Today, this word carries a specific and precise meaning in physics, which is the unit of mass. Thus, the specific heat capacity of a substance is the heat capacity per unit mass (1 kilogram).


specific charge
charge of specification

Quality shipment. It is the charge/mass ratio (Q/m) of a particle. Its unit is the coulon in kilograms. This measurement helps the researcher identify the particle. In Thomson's experiment, the specific charge of the particle was measured using the cathode ray. This led to the knowledge that the particle was an electron.
The Q in an electron is 10-19 x 1.6 coulombs, and m is 9 x 10-30 kilograms. Thus, the specific charge of this particle is 1.8 x 1011 coulombs/kg.


specific heat capacity (c)
Capacity and specific calorie content

Specific heat capacity. The energy involved in changing the temperature of one kilogram of a substance by one degree Celsius. Its unit is joule per kilogram per degree Celsius. The values ​​for ice, water and steam are, respectively, 2.2 kJ/kg°C, 4.2 kJ/kg°C and 1.5 kJ/kg°C.

We can find the specific heat capacity, C, in a certain case using the method of mixtures or using the joule-meter to measure w, and then c = W/mo, where m is the mass of the sample and o is its temperature change.
Also called specific thermal capacity.


specific latent heat (L)
Special latex chaleur

Latent heat capacity. The energy involved in interpreting the state change of one kilogram of matter. See latent heat, its unit is the joule per kilogram (J/kg). The energy W involved in changing the state of a sample whose mass is W=ml. The values ​​of water are equal to 336 kJ/kg (ice/liquid) and 2270 kJ/kg (liquid/vapor). These two values ​​depend on the temperature, and they apply here to the natural temperatures of the state change.
We can find L in a particular case by the method of mixtures or by using the joule-meter to measure W.
Also called thermal capacity.


!
specter m

ghost . A type of graph that shows how types of radiation relate to wavelength (energy). Electromagnetic waves appear on the electromagnetic spectrum, and visible light forms part of it.
See colour.

In the case of electromagnetic waves, the emission spectrum shows the radiation emanating from an actual source. The absorption spectrum shows the radiation absorbed by the material between the source and the detector. Thus, the Sun gives an emission spectrum, and the gases in its atmosphere absorb some wavelengths to give absorption spectra.

The light spectra of simple gases consist of a series of lines called line spectra. Molecules give band spectra. They are groups of converging lines. Hot dense matter gives a continuous spectrum that contains all wavelengths.