λ=mvh=2mKh=2mqVh
λ2λ1=m1m2
λpλe=memp=1831.4=42.79
JEE Main 2021 — Physics Modern Physics
The de-Broglie wavelength associated with an electron and a proton were calculated by accelerating them through same potential of 100V. What should nearly be the ratio of their wavelengths ? (mp=1.00727u,me=0.00055u)
Held on 16 Mar 2021 · Verified 6 Jul 2026.
1860:1
(1860)2:1
41.4:1
43:1
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