λ=mvh
⇒mm′=v′λ′vλ=51×1.8781×10−4×9.1×10−31
m′=9.7×10−28kg
JEE Main 2020 — Physics Modern Physics
A particle is moving 5 times as fast as an electron. The ratio of the de-Broglie wavelength of the particle to that of the electron is 1.878×10–4. The mass of the particle is close to :
Held on 2 Sept 2020 · Verified 6 Jul 2026.
4.8×10−27kg
9.1×10−31kg
1.2×10−28kg
9.7×10−28kg
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