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PhysicsMediumMCQ2021 · 20 Jul Shift 2

Q19.An electron having de-Broglie wavelength λ is incident on a target in a X -ray tube. Cut-off wavelength of emitted X -ray is: (1) 0 (2) 2 m2c2λ2 h2 (3) 2mcλ2 (4) hc h mc

What This Question Tests

This question connects the de-Broglie wavelength of an electron to its kinetic energy, which is then converted into X-ray photon energy to find the cut-off wavelength.

Concepts Tested

De Broglie wavelengthKinetic energy of electronCut-off wavelength of X-rayPhoton energy

Formulas Used

λ_deBroglie = h/p

KE = p^2/(2m)

KE = eV

E_photon = hc/λ_cutoff

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