Electron momentum changes by an amount p and its de Broglie wavelength changes by 0.5%. Initial momentum is:
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Electron momentum changes by an amount p and its de Broglie wavelength changes by 0.5%. Initial momentum is:

G1 Physics · Accepted Answer

λ = h/P implies small relative change |Δλ|/λ ≈ |ΔP|/P. Given |Δλ|/λ = 0.5/100 = 0.005 and |ΔP| = p, initial momentum P ≈ p/0.005 = 200p. Answer: A.