Dipole Moment | MCQs

Explanation

A dipole in an electric field behaves in two ways:

• In a uniform electric field:

The two equal and opposite forces cancel each other out.

So, the net force on the dipole is zero.

But a torque is produced that tends to align the dipole moment parallel to the electric field.

• In a non-uniform electric field:

The dipole does experience a net force, and that force is generally not simply parallel to the field.

So the correct answer remains:

(D) None of these — because in a uniform electric field, the net force on a dipole is zero.

Option (C) would be correct only if we were talking about torque direction or net force in a non-uniform field.

Explanation

Both CS₂ (carbon disulfide) and SO₃ (sulfur trioxide) have zero dipole moment.

Note….: Here CS 2 and SO3 options are correct. However, FPSC did not give a choice of both A and B.

Explanation

Explanation

An electric field exerts a torque on a dipole only if "the field is perpendicular to the dipole moment."

Explanation

The dipole moment of H₂O (water) is approximately 1.83 Debye.

This is due to the bent shape and the difference in electronegativity between hydrogen and oxygen.

Explanation

The molecule that is polar and has a dipole moment of 5.33 x 10^-30 Cm is SO2 (sulfur dioxide).

Explanation

When a dipole with dipole moment $vec{p}$ is placed in an external electric field $vec{E}$, the torque experienced by the dipole is given by:

$$vec{tau} = vec{p} times vec{E}$$

This is a vector cross product, so:

• The magnitude is $tau = pE sintheta$

• The direction is perpendicular to both p​ and E (using the right-hand rule)

Explanation

Dipole moment of H2 =0 ( zero ).

The ionic character exists in H2 molecule but no dipole moment or bond moment exists permanently.

In these diatomic molecules, the shared pair of electrons lies between the nucleus of the two bonded atoms.

Hence, no separation of charges occurs. I.e., these molecules have zero dipole moment.