NEET 2025 · PhysicsElectron-photonPrevious Year Question
A photon and an electron (mass m) have the same energy E. The ratio λ_photon/λ_electron of their de Broglie wavelengths is: (c is the speed of light)
- A.c·√(2m/E)✓
- B.(1/2c)·√(E/m)
- C.√(2E/m)
- D.2c/√(mE)
Correct Answer
(A) c·√(2m/E)
Solution & Explanation
Answer: (a) c·√(2m/E) Solution: Photon: λ_ph = hc/E. Electron: λ_e = h/√(2mE). λ_ph/λ_e = (hc/E)·(√(2mE)/h) = c√(2mE)/E = c·√(2m/E).
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