AIPMT 2010 Physics and Chemistry Paper

According to Coulomb's law, the force of repulsion between the two positive ions each of charge q, separate by a distance d is given by
F=‌

1

4πε0

‌

(q)(q)

d2

F=‌

q2

4πε0d2

q2=4πε0Fd2
q=√4πε0Fd2.........(i)
Since, q= ne
where, n= number of electrons missing from each ion
e= magnitude of charge on electron
∴‌‌n=‌

q

e

n=‌

√4πε0Fd2

e

(using (i))
=√‌

4πε0Fd2

e2