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PhysicsMediumMCQ2025 · 28 Jan Shift 1

Q45.A proton of mass ' mp ' has same energy as that of a photon of wavelength ' λ '. If the proton is moving at non- relativistic speed, then ratio of its de Broglie wavelength to the wavelength of photon is. (1) 1 (2) 1 c √Emp c √2Emp (3) 1 (4) 1 E 2c √Emp c √ 2 mp

What This Question Tests

Assesses the ability to apply de Broglie hypothesis for matter waves and Planck's relation for photon energy, and compare their wavelengths given equivalent energies.

Concepts Tested

de Broglie wavelengthPhoton energyKinetic energy

Formulas Used

E_photon = hc/λ

λ_deBroglie = h/p

KE = p²/(2m)

📚 NCERT Sections This Tests

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