Modern Physics

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Modern Physics

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The retarding potential for having zero photo-electron current

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The momentum of the photon of wavelength 5000A will be

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The momentum of a photon is 3.3×10^-29 kgm/sec Its frequency will be

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The binding energy of the innermost electron in tungsten is 40 keV. To produce characteristic X-rays using a tungsten target in an X-rays tube the potential difference V between the cathode and the anti-cathode should be

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A potential difference of 42,000 volts is used in an X-ray tube to accelerate electrons. The maximum frequency of the X-ray radiations produced is 

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Which of the following wavelength falls in X-ray region?

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 An X-ray tube is operated at 50 kV. The minimum wavelength produced is

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 If the energy of a photon is 25 eV and the work function of the material is 7 eV, then the value of stopping potential is 

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 The momentum of a photon is p. The frequency associated with it is given by

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 Let p and E denote the linear momentum and energy respectively of a photon. If the wavelength is decreased,

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If 𝜆1and 𝜆2 denote the wavelengths of de-Broglie waves for electrons in the first and second Bohr orbits in hydrogen atom, then 𝜆1/𝜆2 is equal to

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A photon of energy of 3.4 eV is incident on a metal having work function 2 eV. The maximum K.E of photoelectrons is equal to

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If E1, E2 and E3 are the respective kinetic energies of an electron, an alpha particle and a proton, each having the same de-Broglie wavelength, then

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The equation E = pc is valid

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 If the wavelength of light incident on the surface of a metal is decreased, the maximum velocity of emitted photo-electrons will

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The mass of a photon at rest is

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Dual nature of radiation is shown by

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The free electrons from a metal surface can be taken out by the process 

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The radius of electron's second stationary orbit in Bohr's atom is R. The radius of the third orbit will be 

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Wave nature of light appears in

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The energy of a photon is 3 x 10^-19 J. Its momentum is

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A radio station emits 10 kW power of 90.8 MHz. Find the number of photon emitted second 

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 The curve drawn between velocity and frequency of photon in vacuum will be a: 

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Ratio of momentum of photons having wavelength 4000 angstrom and 8000 angstrom is

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The velocity of a particle of mass m of de-Broglie wavelength λ is___

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  If the wavelength of incident radiation in a photoelectric experiment is decreased then

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What is the de Broglie wavelength of a proton whose linear momentum has a magnitude of 3.3 × 10^-23 kgm/s?

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A Balmer line is emitted when the electron in a hydrogen atom jumps from

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The classical theory cannot explain the dependence of photo emission on

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Number of the emission spectra are

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The experimental value of Rydberg constant is

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The ratio of the K.E & the P.E of electron in hydrogen atom will be.

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An electron of hydrogen is present in the -3.4 eV energy state. Find the angular momentum of the electron.

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A photon whose energy is Ep joules strikes a photosensitive surface whose work function is ⲫjoules. The maximum energy of the ejected photoelectron is equal to

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 If the electron in a hydrogen atom jumps from the third orbit to second orbit the emitted radiation has wavelength

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Stopping potential does not depend upon 

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Kinetic energy of electrons by applying potential difference Vi across the X-ray tube is KE, while V2 potential difference produces kinetic energy equal to KE2. What will be the value of KE1: KE2 if ratio of potential difference V₁:V₂ = 2:3?

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Characteristic X-rays are produced by energy changes in

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 (K.E.)max= hf-hf0, is known as:

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High energy photon emitted due to transition of inner shell electrons in heavy atom are called

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When electrons lose their all K.E in striking target, then X-rays having K.E

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 X-ray region is situated between

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X-rays cannot produce

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 Electrons of mass m and charge e are accelerated through a potential difference V and strike the target. The maximum speed of these electrons is

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 If anode potential of increase then

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If the incident electrons in Coolidge tube are accelerated through a potential of V volt, then the maximum frequency of continuous X-rays will be

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 Water is circulated in Coolidge tube to

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 X-rays are absorbed maximum by?

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For harder X-rays 

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 Consider a photon of continous X-rays coming from a Coolidge tube. Its energy comes from

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Who discovered X-rays?

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