Question

An electric dipole is placed at an angle of 30° with an electric field intensity 2 × 10⁵ N/C. It experiences a torque equal to 4 N m. The charge on the dipole, if the dipole length is 2 cm, is
(1) 8 mC
(2) 2 mC
(3) 5 mC
(4) 7 µC

Answer 1

Explanation:

Here dipole moment , p=lq=(2/100)q=0.02q

Now, torque , τ=pEsinθ

or 4=(0.02q)(2×105)sin30

or q=200×10−5C=2mC

Answer 2

Answer:

the answer is option b (2 mC)