Two dipoles `vecP_(1)` and `vecP_(2)` are oriented as shown in the figure. Assuming dipole of dipole moment `vecP_(2)` to be placed at origin and dipole of moment `vecP_(1)` is at a distance `'d'` from origin then

Options

A. Torque experienced by `vecP_(1)` is `-(1)/(8piepsilon_(0))(P_(1)P_(2))/(d^(3))hatk`
B. Torque experienced by `vecP_(1)` is `+(1)/(4piepsilon_(0))(2P_(1)P_(2))/(d^(3))hatk`
C. Torque experienced by `vecP_(1)` is `-(1)/(4piepsilon_(0))(P_(1)P_(2))/(d^(3))hatk`
D. Torque experienced by `vecP_(1)` is `+(1)/(4piepsilon_(0))(P_(1)P_(2))/(d^(3))hatk`

Explanation

`vectau_(1)=vecP_(1)xxvecE=(P_(1))hatjxx((2P_(2))/(4piepsilon_(0)d^(3)))hati=(2P_(1)P_(2))/(4piepsilon_(0)d^(3))hatk`
`vectau_(2)=vecP_(2)xxvecE=(P_(2))hatixx(-(P_(1))/(4piepsilon_(0)d^(3)))hatj=-(P_(1)P_(2))/(4piepsilon_(0)d^(3))hatk`