Formula for velocity of electrons in orbit is
Vn= Ze^2/2nh
e= charge on electron
Z= Atomic number
n= no. orbit
h= Plank’s constant
First orbit of the H atom given as follows:
V= x
V1= 1*e^2/2*1*h
=e^2/2h=x
For the 3rd orbit
V3= 1*e^2/2*3*h
=e^2/6h=1/3x
(e2/2h*1/3=x*1/3 becomese2/6h=1/3x).
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