Consider a positively charged infinite cylinder with uniform volume charge density \(r > 0\). An electric dipole consisting of \(+Q\) and \(-Q\) charges attached to opposite ends of a massless rod is oriented as shown in the figure. At the instant as shown in the figure, the dipole will experience,

• A

  a force to the left and no torque
• Correct answer
  B

  a force to the right and a clockwise torque
• C

  a force to the right and a counter clockwise torque
• D

  non froce but only a clockwise torque

Solution

Hint :

\(E \propto \frac{1}{r}\) \(\begin{aligned} & \mathrm{F}_1 > \mathrm{F}_2 \\ & \therefore \quad \mathrm{F}_{\text {net }} \text { towards right } \tau_{\text {net }} \text { clockwise. }\end{aligned}\)

Hence, the correct answer is option: 'B'.