An electric dipole is placed at an angle of 30 ° with an electric...

Torque experienced by the electric dipole is given by,

$\left|\overset{\to}{τ}\right| = \left|\overset{\to}{p} \times \overset{\to}{E}\right| ⇒ 4 = pEsin\theta ⇒ 4 = \left(ql\right) \times \left(2 \times {10}^{5}\right) \times \sin 30 ° ⇒ q = \dfrac{4}{{10}^{5} \times \left(2 \times {10}^{- 2}\right)} = 2 \times {10}^{- 3}C = 2mC$