JEE Main20257 Apr 2025Evening ShiftPhysicsElectrostaticsActual
A dipole with two electric charges of 2 C magnitude each, with separation distance 0.5 ~m , is placed between the plates of a capacitor such that its axis is parallel to an electric field established between the plates when a potential difference of 5 V is applied. Separation between the plates is 0.5 mm. If the dipole is rotated by 30^ from the axis, it tends to realign in the direction due to a torque. The value of
Options
- A5 10⁻⁹ Nm
- B5 10⁻³ Nm
- C2.5 10⁻¹² Nm
- D2.5 10⁻⁹ Nm
Correct answer
A. 5 10⁻⁹ Nm
Step-by-step solution
aligned & E = v ~d = 5 5 10⁻⁴ =10^4 ~V / m & = PE aligned Where P = qa =2 10⁻⁶ 5 10⁻⁷ =1 10⁻¹² C - m =1 10⁻¹² 10^4 1 2 =5 10⁻⁹ ~N - m