Net torque, electric dipole confusion

[Bengo]

Hello all,

I am so confused on why a net torque on a dipole in a uniform electric field would not be equal to zero. Wouldn't one end rotate clockwise, the other counterclockwise and cancel out to zero?

Thanks.

 

[Doc Al]

Since each pole has an opposite charge and thus feels an opposite force, each tends to turn in the same direction. The net force cancels, but the torque does not.