Question

If $E_{1}$ be the electric field strength of a short dipole at a point on its axial line and $E_{2}$ that on the equatorial line at the same distance, then

• A. $E_{1}=E_{2}$
• B. $E_{1}=2E_{2}$
• C. $E_{2}=2E_{1}$
• D. None of the above

Answer 1

Answer: (B)

$E_{1}=2E_{2}$

Answer 2

The electric field strength in end on position, is given by
$E_{1}=\frac{1}{4 \pi \varepsilon_{0}} \cdot \frac{2 p}{d^{3}}$ ...(i)
Electric field strength on broad side on position or on equatorial position is
$E_{2}=\frac{1}{4 \pi \varepsilon_{0}} \frac{p}{d^{3}}$ ...(ii)
From Eqs. (i) and (ii), we get
$\frac{E_{1}}{E_{2}}=\frac{2}{1}$
$\Rightarrow E_{1}=2 E_{2}$