Question

Example 53. Calculate the electric field due to an electric
dipole of length 10 cm having charges of 1 uC at an equatorial
point 12 cm from the centre of the dipole.​

Answer 1

Therefore the Electric field due to an electric dipole is 4.1 × 10^5 N/C.

Given : An electric dipole of length 10cm having charge of one micro coulomb at an equatorial point 12cm from the centre of the dipole.

To find : The electric field due to the electric dipole.

solution : The electric field due to an electric dipole is given by, E = KP/(r² + a²)³/²

where P = q2a = 10^-6 C × 10 × 10^-2 m = 10^-7 Cm

r = 12 cm = 0.12 m and a = 5cm = 0.05 m

The electric field, E = (9 × 10^9 × 10^-7)/[(0.12)² + (0.05)²]³/²

= (900)/[0.0144 + 0.0025]³/²

= 900/(0.0169)³/²

= 900/(0.13)³

= 900/0.002197

= 409,649.522

≈ 4.1 × 10^5 N/C

Therefore the Electric field due to an electric dipole is 4.1 × 10^5 N/C.