An electric dipole consists of two opposite charges each 0.05 μC separated by 30 mm. The dipole is placed in an uniform external electric field of 106 NC - 1. The maximum torque exerted by the field on the dipole is

Question

An electric dipole consists of two opposite charges each 0.05 μC separated by 30 mm. The dipole is placed in an uniform external electric field of 106 NC - 1. The maximum torque exerted by the field on the dipole is (A)  6 × 10 - 3 N -m - 1 (B)  3 × 10 - 3 N -m - 1 (C)  15 × 10 - 3 N -m - 1 (D)  1.5 × 10 - 3 N -m - 1

Tardigrade Admin · Accepted Answer

Given q = 0.05 μ C = 5 × 10 - 8 C 2a = 30 nm = 0.03 m E = 106 NC - 1 Torque acting on an electric dipole placed in an uniform electric field τ = pE sin θ For maximum torque θ = 90° ∴ τ max = pE = E ( q × 2a) = 106 × 5 × 10 - 8 × 0.03 = 1.5 × 10 - 3 N -m - 1

Q. An electric dipole consists of two opposite charges each 0.05 $μ$ C separated by 30 mm. The dipole is placed in an uniform external electric field of $1 0^{6} N C^{- 1}$ . The maximum torque exerted by the field on the dipole is

$6 \times 1 0^{- 3} N - m^{- 1}$

$3 \times 1 0^{- 3} N - m^{- 1}$

$15 \times 1 0^{- 3} N - m^{- 1}$

$1.5 \times 1 0^{- 3} N - m^{- 1}$

$9 \times 1 0^{- 3} N - m^{- 1}$

Q. An electric dipole consists of two opposite charges each 0.05 μC separated by 30 mm. The dipole is placed in an uniform external electric field of 106NC−1. The maximum torque exerted by the field on the dipole is

6×10−3N−m−1

3×10−3N−m−1

15×10−3N−m−1

1.5×10−3N−m−1

9×10−3N−m−1