Question

Please give me explanation of the question 5 shared below

Answer 1

We know that Coloumb's Force is given as

$F_{columbs}=k\frac{|q_{1}|\:\:|q{2}|}{r^{2}}$

Here Force is in Newton (N)

r is in metre (m)

q is in coloumbs (C)

Then k is equal to .

$k=\frac {F×r^{2}}{q^{2}}$

$k=\frac{N×m^{2}}{C^{2}}$

Hence unit of k

$k\:or\: \frac{1}{4\pi\epsilon _{o}}=Nm^{2}C^{-2}$