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What is Compton effect?
Important Questions on Photoelectric Emission and Production and Properties of X-rays
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Two sources of light emit X-rays of wavelength and visible light of wavelength , respectively. Both the sources emit light of the same power . The ratio of the number density of photons of X-rays to the number density of photons of the visible light of the given wavelengths is:
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Two particles move at right angle to each other. Their de Broglie wavelengths are and respectively. The particles suffer perfectly inelastic collision. The de Broglie wavelength of the final particle, is given by:
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A laser operates at a wavelength of . The number of photons that will be emitted per second is:
[Given Planck's constant speed of light ]
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To excite the spectral line of wavelength of an atom, an excitation energy of is required. The ground state energy of the atom is . The energies of two levels involved in the emission of line are (Assume, , where is Planck's constant and is speed of light)
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A pulse of light of duration is absorbed completely by a small object initially at rest. Power of the pulse is and the speed of light is . The final momentum of the object is
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A photodiode sensor is used to measure the output of a lamp kept away The sensor has an opening of in diameter. How many photons enter the sensor if the wavelength of the light is and the exposure time is . (Assume that all the energy of the lamp is given off as light and )
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Light is incident normally on a completely absorbing surface with an energy flux of . If the surface has an area of , the momentum transferred to the surface in time duration will be:
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The momentum of a photon is . Its frequency will be
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A light source is radiating light of wavelength uniformly in all directions. The photon flux at a distance of is of the order of (Planck's constant,
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A infrared source is radiating light of wave length uniformly in all directions. The photon flux at a distance of is the order of
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A monochromatic source of radiation is operating at power. The source emits photons per second. The wavelength of light will be
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An electron and a photon have the same wavelength of If E is the energy of the photon and p is the momentum of the electron, the magnitude of in S.I. units is,
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The wavelength of photon is What is the frequency of photon?
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A light beam of intensity is incident normally on a perfectly reflecting surface of sides . The momentum imparted to the surface by the light per second is
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The number of photons falling per second on a completely darkened plate to produce a force of is . If the wavelength of the light falling is then
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If the energy of photons corresponding to wavelength of is . The photon energy for wavelength of will be _____
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Given below are two statements:
Statement Two photons having equal linear momenta have equal wavelengths.
Statement If the wavelength of the photon is decreased, then the momentum and energy of a photon will also decrease.
In the light of the above statements, choose the correct answer from the options given below.
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A (kilo-watt) laser beam of wavelength is used to levitate a thin aluminium disk of same area as the cross-section of the beam. The laser light is reflected by the aluminium disk without any absorption. The mass of the foil is close to,
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Some energy levels of a molecule are shown in the figure. The ratio of the wavelengths , is given by:
HARD
A photon of wavelength is absorbed by an electron confined to a box of length , As a result, the electron makes a transition from state, to the state, Subsequently, the electron transits from the state to the state by emitting a photon of wavelength Then
