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What is difference between excitation and ionization potentials?

Excitation potential: The potential required to lift an electron from ground state to some higher state is called excitation potential. Or If the energy supplied to an electron is such that the electron is lifted from its ground state to one of the higher allowed orbits,the atom will be excited and the energy supplied is called excitation energy or excitation ...

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What are some applications of a step up transformer?of a step down transformer?

Applications of a step up transformer: For Transmission of electric power from power station to consumer,voltage is step up by using step up transformer.It minimizes the power loss in transmission line. Applications of a step down transformer: Step down transformer decrease the voltage to a safe value at the end of the transmission line where the consumer of electric power ...

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Why would power distribution systems be less effective without alternating current?

Most larger power distribution systems are AC.The power is transmitted from power stations at much higher voltage to minimize the power loss.At the end of the line where the consumer is located,the voltage level is reduced to a safe value for domestic use.The crucial factor is that it is much easier to increase and decrease AC voltage than DC,so AC ...

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Definition of motion in physics

Motion and its types physics: “A body is said to be in motion,if it changes its position with respect to its surroundings.” Surroundings are the places in its neighborhood where various objects are present.The state of rest or motion of a body is relative.For example,a passenger sitting in a moving bus is at rest because he is not changing his ...

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Moment of inertia units

Moment of inertia: Moment of inertia is defined as:”The sum of the products of the mass of each particle of the body and square of its perpendicular distance from axis.”For a rigid body moving about a fixed axis,the laws of motion have the same form as those of rectilinear motion,with moment of inertia replacing mass,angular replacing linear velocity,angular momentum replacing ...

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Ultrasound frequency range

What is ultrasonics? The study and application of mechanical vibrations with frequencies beyond the limits of hearing of the human ear i.e ,with frequencies about 20 kHz and upwards.There is no theoretical upper limit to the ultrasonic frequency ,although ultrasonic applications are usually restricted to about 20 MHz.Ultrasonic waves have the same basic properties as sound waves,both being examples of ...

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Hall effect semiconductor

What is the Hall effect? “An effect when occurring when a current carrying conductor is placed in a magnetic field and orientated so that the field is at right angles to the direction of the current.”An electric field is produced in the conductor at right angles to both the current and the magnetic field.The field produced is related to the ...

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Does the sun do any work on earth?

No work is done on the earth revolving around it in perfectly circular orbit.The earth revolves around the sun due to gravitational force of attraction between the sun and the earth.This gravitational force provides centripetal force to the earth to revolve around the sun.Since centripetal force is always directed towards the centre of the orbit.This centripetal force is always perpendicular ...

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Is energy quantized in classical physics?

No,according to classical wave theory the emission of electromagnetic radiations from the surface is continuous. So energy is not quantized in classical physics.But according to photon theory the emission of electromagnetic radiation from the surface is discontinuous.Energy is quantized and radiations are emitted in the form of bundles of energy is called quanta or photon.Each photon has energy given as: ...

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bohr model for hydrogen

 Bohr’s theory of the  hydrogen atom: The Rutherford model of atom and the experimental formula of atomic spectra helped Bohr is solving the problem of atomic structure.In 1913 he proposed a model for the structure of a hydrogen atom based on his experimental observations.  Bohr’s postulates: Neil Bohr based his theory of hydrogen atom on the following three postulates. 1:The ...

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