Question

For a dipole, q = 2 x 10-6 C and d = 1 cm. The
external electric field if maximum torque
experienced by this dipole 10-2 Nm, is
(1) 15 x 10-5 N/C (2) 5 x 105 N/C
(3) 3 x 10-4 N/C (4) 3104 N/C

Answer 1

Answer:

5 x 10^(5) N/C

Explanation:

Dipole moment(p) = 2lq = dq

Dipole moment = (1cm)(2 x 10^(-6))

Dipole moment = 2 x 10^(-8) C m

Let the electric field(E) be E.

Using torque = p x E (vector product)

=> torque = pEsin∅

For torque to be maximum, sin∅ must be maximum i.e. 1.

=> max. torque = pE(1)

=> 10^(-2) = 2 x 10^(-8) × E

=> (1/2) x 10^(6) = E

=> 5 x 10^(5) = E