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

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

farad
farad m

If a charge of one coulomb changes its potential by one farad, the conductor will have a capacitance (see capacitor) of one farad.

C = Q/V


Faraday
Faraday

Faraday Michael Faraday (1791 - 1861) was a student of Humphrey Davy, and he accomplished much important work in the fields of physics and chemistry. His main research topics in physics were: electromagnetic induction, electromagnetic induction, generators, magnetic fields, electrolysis, and the polarization of light. His name was immortalized in the farad, a unit
Capacitance. See capacitor.


fiber optics
fibres mpl optiques

Fiber optics. A technology in which signals are transmitted by light waves through optical tubes confined by total internal reflection. Light waves can carry much more data than currents in wires. While the glass used must be extremely pure, it is still cheaper and lighter than copper wire. Hence, a fiber with a hair's breadth can transmit telephone communications or television channels as much as it can transmit a thick copper cable.


field. field
champ m

field. An area of ​​space in which the relevant forces appear. Thus, a magnetic field is a region in which magnetic forces exist. Just as force is a vector, a force field is a vector field, and has magnitude and direction at each of its points. The so-called lines of force (field lines) are often used to describe force fields, and these lines, with their direction and convergence, show the direction of the field and its strength at every point.

filament
file m

rite. The name of the thin, high-resistance wire in an ordinary light bulb. This wire is usually made of tungsten and becomes white hot when current passes through it. The filament is used in a cathode ray valve to provide heat to the cathode or sometimes to act as a cathode as well. It releases electrical charges and is attracted by the elevator.


filter
filter m

candidate . 1 - In optics: a piece of material that does not pass more than one band of wavelengths while absorbing the other bands. Thus the green filter only passes green. See absorption and colour.

2 - An electronic circuit that passes alternating current better at some frequencies than at others.

There are three types of filters, as shown in the drawings below. In each case, we show the relationship of the passing current to the frequency input. The low-pass filter (A) transmits direct current and low-frequency alternating current well, but it blocks high frequencies. The high-pass filter does the opposite (b). As for the band-pass filter shown in (c), it only transmits alternating current within
A field, or a specific range of frequencies.


fission
fission f

Dichotomy . A form of radioactivity in which an unstable nucleus splits into two approximately equal parts. There is a transfer of energy to these two parts and to the two or three neutrons that also appear.

Neutron
Neutron
Neutron

A well-known case is that of 235U, the lightest common isotope of uranium. If a 235U nucleus absorbs a neutron, it becomes 236U, which is a very unstable isotope that splits quickly. The effect may be as follows:

235/92U + 1/0n → 236/92U

Energy + 31/0n + fission products →
If there is enough 235U in the sample, a chain reaction can occur. Fission is used in the atom bomb and in nuclear power plants due to the effectiveness (yield) of mass-energy transfer.