Two opposite and equal charges $4 \times 10^{-8} \, C$ are placed $2 \times 10^{-2} \, cm$ apart,forming a dipole. If this dipole is placed in an external electric field of $4 \times 10^8 \, N/C$,what are the values of the maximum torque and the work done in rotating it through $180^\circ$?

• A
  $64 \times 10^{-4} \, Nm$ and $64 \times 10^{-4} \, J$
• B
  $32 \times 10^{-4} \, Nm$ and $32 \times 10^{-4} \, J$
• C
  $64 \times 10^{-4} \, Nm$ and $32 \times 10^{-4} \, J$
• D
  $32 \times 10^{-4} \, Nm$ and $64 \times 10^{-4} \, J$