Showing posts with label ideal gas. Show all posts
Showing posts with label ideal gas. Show all posts

PHYSICS DICTIONARY

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Ice Point

The temperature, equal to 0 oC, at which pure water and ice are in equilibrium in a mixture at 1 atmosphere of pressure is called as ice point. Ice point is most important fixed point for defining temperature scales and for calibrating thermometers.


Ideal Fluid

Fluid is called as ideal fluid if it has zero viscosity, zero compressibility and its flow should be irrotational and steady.


Ideal Gas

It is the gas which perfectly obeys Boyle’s law and Charles law.


Identical Particles

If two particles are identical, no observable effects whatever can arise from interchanging them.  More precisely, all observable quantities must remain unaltered if the position, momentum and other dynamical variables such as spin of first particle are interchanged with those of second particle. 


Illumination

Process of focusing light on to something to make it visible or bright is called as illumination.


Image

It is an optically formed duplicate counterpart or other representative reproduction of an object, especially an optical reproduction formed by lens or mirror.

                                                 or

Optical appearance or counterpart produced by light from an object reflected in mirror refracted through lens.   


Imaginary Number

It is mathematical quantity of the form iX, where ‘X’ is real number. ‘I’ is unit imaginary number and   i2 = -1.


Impedance

Characteristic of alternating current circuit made of two components: “resistance” and “reactance”,  which is a measure of total opposition to current flow. It is usually represented as Z= R+iX, where ‘R’ is ohmic resistance and ‘X’ is reactance.


Impulse

It is defined as change in momentum when large force acts for short time interval.


Impurity Diffusion

Process, where by atoms of one metal diffuse into another is termed as impurity diffusion.

 

Incandescence

Property of hot body which emits visible electromagnetic radiation by virtue of its temperature.


Independent Variable

Variable who values are independent of changes in the values of other variables. 

                                                          Or

Variable whose value determines the value of other variables.


Indirect Band Semiconductor

The semiconductor in which an electron in  conduction band (minimum) cannot fall to valence band maximum but must undergo change in momentum, which may be caused by traps in energy gap. Generally, the energy difference is given up as heat to lattice.


Indirectly Ionizing Radiation

It Comprises neutral particles (such as photons, X-rays, neutrons) that deposit energy in the absorber through a two-step process as follows: In the first step a charged particle is released in the absorber (photons release either electrons or electron/positron pairs; neutrons release protons or heavier ions). In the second step, the released charged particles deposit energy to the absorber through direct Coulomb interactions with orbital electrons of the atoms in the absorber.


Induced Charge

When a charged object is put close to a neutral object, charges are induced on the surface of the neutral object and are called induced charges.


Inductance

The energy density is proportional to the square of the magnetic field strength, which is in turn proportional to the current flowing through the coiled wire, so the energy stored in the inductor must be proportional to square of the current. The constant of proportionality is called as inductance. The unit is joules per ampere squared, abbreviated as Henry.


Induction

Concept discovered by Faraday in 1831. Any electric field that changes over time will produce magnetic field in space around it                                              

                                                               or

any magnetic field that changes over time will produce an electric field in the space around it.


Induction Coil

The induction coil was invented in the late nineteenth century as a source of high voltage for laboratory experiments. Induction coil is a device for converting low-voltage direct current (DC) into high-voltage alternating current (AC). It is a single coil of conductive material, often surrounding a metallic core, designed to establish a strong magnetic field around the coil. Changes in the current flow through the coil cause fluctuations in the magnetic field that induce a voltage across the coil. Induction coils are used for many purposes, especially as spark coils for firing spark plugs in automobile engines and starting oil burners.

Perfect Gas Law

In the kinetic theory of gases, an ideal gas is one in which the individual molecules are sufficiently far apart that the short range force that acts between them can be ignored. Collisions between molecules are assumed to be perfectly elastic.

Laboratory experiments have shown that for such a gas there is a simple equation of
state relating the pressure p, absolute temperature T, and volume V. For m kilograms of
gas, this equation may be written
pV = mRT,
where R is a constant for the particular gas. R is called the gas constant and has units of
Joules per degree per kilogram.

We define a kilogram-molecular weight, or kilomole (abbreviated kmole) of a material
as its molecular weight expressed in kilograms. (Older texts define molecular weight as
the molecular weight expressed in grams).

For example, the molecular weight of water is 18.016, and therefore one kilomole of water is 18.016 kg of water. The number of kilomoles n in mass m (in kilograms) of material is given by

n = m/M.

Where M is the molecular weight. One kilomole of any material is equal to the weight of a single molecule (in kg) times the number of molecules, N. This number is called Avogadro's number and has the value 6.022 ×1026 (for a kmol of substance).

Avogadro hypothesized that gases containing the same number of molecules occupy the same volume at the same pressure and temperature. This implies that for one kilo mole of any gas
pV = MRT

Accordingly, R* = MR is a universal constant for all gases. It is called the universal gas constant and has the value 8314.3 J deg −1 kmol −1 .