At the distance of the lowest approach, total K.E. of α-particle changes to P.E. So,
21mv2=rKQ.q=rK(Ze)(2e)
r=mv24KZe2⇒r∝m1
r∝m1
When an α -particle of mass m moving with a undefined velocity bombards on a heavy nucleus of charge Ze, its distance of the closest approach from the nucleus depends on m as:
Held on 30 Apr 2016 · Verified 9 Jul 2026.
m1
m1
m21
m
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