21(4m)v2+21(180m)(1804v)2=5.5MeV
⇒214mv2[1+45(1804)2]=5.5MeV
⇒K.E.α=1+45⋅(1804)25.5MeV=5.38MeV
JEE Main 2021 — Physics Modern Physics
A nucleus with mass number 184 initially at rest emits an α−particle. If the Q value of the reaction is 5.5MeV, calculate the kinetic energy of the α− particle.
Held on 22 Jul 2021 · Verified 6 Jul 2026.
5.0MeV
5.5MeV
0.12MeV
5.38MeV
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