An electric dipole is kept on the axis of a uniformly charged ring at distance R/√2 from the centre of the ring. The direction of the dipole moment is along the axis. The dipole moment is P , the charge of the ring is Q and the radius of the ring is R . The force on the dipole is nearly

Question

An electric dipole is kept on the axis of a uniformly charged ring at distance R/√2 from the centre of the ring. The direction of the dipole moment is along the axis. The dipole moment is P , the charge of the ring is Q and the radius of the ring is R . The force on the dipole is nearly (A) â (4 k P Q/3 √3 R2) (B) (4 k P Q/3 √3 R3) (C) (2 k P Q/3 √3 R3) (D) Zero

Tardigrade Admin · Accepted Answer

At x = (R/√2) , the electric field due to the ring is maximum. The force on a dipole in a non-uniform field is F=p(d E/d x) But at the point of maxima, (d E/d x)=0 This means F=0

Q. An electric dipole is kept on the axis of a uniformly charged ring at distance $R / 2$ from the centre of the ring. The direction of the dipole moment is along the axis. The dipole moment is $P$ , the charge of the ring is $Q$ and the radius of the ring is $R$ . The force on the dipole is nearly

$\frac{4 k PQ}{3 3 R ^{2}}$

$\frac{4 k PQ}{3 3 R ^{3}}$

$\frac{2 k PQ}{3 3 R ^{3}}$

Zero

At $x = \frac{R}{2}$ , the electric field due to the ring is maximum.
The force on a dipole in a non-uniform field is
$F = p \frac{d E}{d x}$
But at the point of maxima, $\frac{d E}{d x} = 0$
This means $F = 0$

Q. An electric dipole is kept on the axis of a uniformly charged ring at distance R/2​ from the centre of the ring. The direction of the dipole moment is along the axis. The dipole moment is P , the charge of the ring is Q and the radius of the ring is R . The force on the dipole is nearly

​ 33​R24kPQ​

33​R34kPQ​

33​R32kPQ​