An electric dipole is placed at an angle of 30 ° with an electric field of intensity 2 × 10 5   N   C - 1 . It experiences a torque equal to 4   N   m . Calculate the magnitude of charge on the dipole, if the dipole length is 2   cm .

Step-by-step solution

Torque experienced by the electric dipole is given by, τ → = p → × E → ⇒ 4 = p E sin θ ⇒ 4 = q l × 2 × 10 5 × sin 30 ° ⇒ q = 4 10 5 × 2 × 10 - 2 = 2 × 10 - 3   C = 2   mC