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Question
Two photons of
Options
equal wavelength have equal linear momenta
equal energies have equal linear momenta
equal frequencies have equal linear momenta
equal linear momenta have equal wavelengths
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Solution
equal linear momenta have equal wavelengths
Two photons having equal linear momenta have equal wavelengths is correct. As in the rest of the options magnitude of momentum or energy can be same because energy and momentum are inversely proportional to wavelength. But the direction of propagation of the photons can be different.
Hence the correct option is D.
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