Momentum (p) of each electron λ1hi^ and λ2hj^ Velocity of centre of mass Vcm=2 mλ1hi^+2 mλ2hj^(∵p=mv) Velocity of 1 st particle about centre of mass V1 cm=2 mλ1hi^−2 mλ2hj^ λcm=4λ12h2+4λ22h2h=λ12+λ222λ1λ2(∵λ=ph)
JEE Main 2018 — Physics Modern Physics
Two electrons are moving with non-relativistic speeds perpendicular to each other. If corresponding de Broglie wavelengths are λ1 and λ2, their de Broglie wavelength in the frame of reference attached to their centre of mass is:
Held on 15 Apr 2018 · Verified 6 Jul 2026.
λCM=λ1=λ2
λ11=λ11+λ21
λCM=λ12+λ222λ1λ2
λCM=(2λ1+λ2)
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