An electric dipole is kept in an electric field which is increasing in +x direction. The dipole moment of the dipole is also along the +x direction. Which of the following options is correct for the electric dipole. |
Electric dipole will not experience any force in the presence of the electric field ($\vec E$). Electric dipole will experience force and try to align perpendicular to the direction of electric field ($\vec E$). Electric dipole will experience a net force in +x direction. Electric dipole will experience a net force in -x direction. |
Electric dipole will experience a net force in +x direction. |
The correct answer is Option (3) → Electric dipole will experience a net force in +x direction. Given: Electric field $\mathbf{E}$ increases along +x, and dipole moment $\mathbf{p}$ is also along +x. Force on positive charge: $+qE_+$ (toward +x) Force on negative charge: $-qE_-$ (toward −x) Since $E_+ > E_-$, net force acts in the direction of increasing field, i.e. +x direction. Therefore, the dipole experiences: • No torque (because $\mathbf{p} \parallel \mathbf{E}$) • A net force in the +x direction Hence, the dipole experiences a net force along +x but no torque. |