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Difference between conduction,convection and radiation

There are three modes of heat transfer,conduction,convection and radiation.In the process of conduction heat transfer from hot body to cold body due to free electrons.In convection heat transfer due to actual movement of molecules,While in radiation heat transfer in the form of electromagnetic waves. There are three different ways of heat transfer.If you learn difference between conduction,convection and radiation,then you ...

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Conduction heat transfer examples and applications

convection heat transfer Radiation heat transfer “The mode of transfer of heat by vibrating atoms and free electrons in solids from hot to cold parts of a body is called conduction of heat.” The handle of the metal spoon held in hot water soon gets warm. But in case of a wooden spoon, the handle does not get warm. Both ...

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Special and general theory of relativity

Theory of Relativity The theory of relativity is concerned with the way in which the observers who are in a state of relative motion describe the physical phenomenon. Theory of relativity is given by Albert Einstein in 1905 which states that there is no absolute state exist in the universe, all states are relative. The theory of relativity is concerned ...

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Fundamental units and their definitions

Units The fixed and definite quantity taken as the standard of reference with which other quantities of the same kind are measured is defined as a “unit”. Fundamental Units The units of fundamental quantities are called “fundamental units”. For example, units of length, mass and time or those of fundamental units. Table lists all fundamental and supplementary units and their ...

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Types of physical quantities

  These are quantities that are used to describe the laws of physics. Physical quantities may be divided into six categories. Constant or ratio Such quantities have the only magnitude, for example, refractive index, dielectric constant and specific gravity. Such quantities have no units. Scalars These quantities have magnitude and unit. Some of them may have direction also but vector ...

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Properties and applications of laser light

Properties of laser light Laser light is highly monochromatic Tungsten light spread over a continuous spectrum, gives no basis for comparison. The light from selected lines in a gas discharge tube (line spectrum) however can have wavelengths in the visible region that are precise to about 1 part in 106. The sharpness of definition of laser light can easily be ...

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Difference between resistance and resistivity in tabular form

Resistance and resistivity difference                     Resistance                          Resistivity  It is the opposition to the flow of electric current through a conductor. It is the resistance of a meter cube of a wire. Its SI unit is ohm ( Ω ). Its ...

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Galvanometer and ammeter

Galvanometer and ammeter are both current measuring devices.The galvanometer is used to measure very small current while ammeter is used to measure very large current up to 10 A. Now! We study in detail about these two instruments and we will also see the difference between galvanometer and ammeter. What is galvanometer? It is an electrical device which is used to ...

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Types of radioisotopes and their uses in medicine & agriculture

Nuclei which do not emit radiations naturally are called stable nuclei. In general, most of the nuclei with atomic number 1 to 82 are stable nuclei. While the elements whose atomic number is greater than 82 are naturally unstable. They emit different types of radiations, all the time, and hence continuously change from one type of element to another.The stable ...

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Ammeter and voltmeter

An ammeter is an electrical device which is used to measure the current. It is the modified form of the galvanometer. It is a low resistance galvanometer. It is always connected in series with the circuit to measure current. An ideal ammeter has zero resistance. Meter movement The portion of galvanometer whose motion causes the needle of the device to ...

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