Answer to Question #191411 in Electricity and Magnetism for Hanatayuji

Question

Given the dielectric constant of water 80. If the average molecular magnetic dipole moment of water is 6.2×10^-30 cm. Determine polarisation and electric field?

Answer 1

Answer

Bond lenth of O-H

$d=0.94\times10^{-10}m$

Angle between two O-H bond =52.5°

Dipole moment is given by

$p=ed$

e= polarity of molecule

d=distance between molecule

Distance between molecule

D=dcos52.5°

So polarity can be obtain as

$e=\frac{p}{dcos52.5°}$

So

$e=\frac{6.2\times10^{-30}}{(0.94\times10^{-10})cos52.5°}=1.08\times10^{20}C$

Electric field due to dipole can be obtain as by formula below

$E=\frac{Kp}{(4\pi \epsilon _0r3)}\\E=\frac{5.58\times10^{-21}}{r^3} N/C$