An electric dipole consists of two opposite charges each of magnitude `1 muC` separated by `2 cm`. The dipole is placed in an external uniform field of `10^5 NC^-1` intensity. Find the
a. maximum torque exterted by the field on the dipole, and
b. work done in rotating the dipole through `180^(@)` starting from the position `theta = 0^(@)`.

Answer

2

Explanation

Here, `q = 1m C = 10^(-3)C`,
`2a = 2 cm = 2xx10^(-2) m`,
`E = 10^(5) N//C`
Maximum torque, `tau = pE = q (2a) E`
`= 10^(-3) (2xx10^(-2))xx10^(5)`
`= 2 N.m`