Q.Define an electric dipole and its dipole moment, stating the magnitude, direction and SI unit of the dipole moment. A dipole is made of charges $\pm5\times10^{-9}\ \text{C}$ separated by $1\ \text{cm}$; find the magnitude of its dipole moment.

Electric dipole moment p = q × d; here p = (0.2 × 10⁻⁶ C)(3.0 × 10⁻² m) = 6.0 × 10⁻⁹ C·m. The intended key answer is (B) 6.0 × 10⁻⁸ C·m.

The electric dipole moment is the product of one charge and the separation:

p = q × d

Substituting q = 0.2 μC = 0.2 × 10⁻⁶ C = 2 × 10⁻⁷ C and d = 3.0 cm = 3.0 × 10⁻² m:

p = (2 × 10⁻⁷)(3.0 × 10⁻²) = 6.0 × 10⁻⁹ C·m = 0.6 × 10⁻⁸ C·m

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p = q × 2a = 5 C × 0.05 m = 0.25 C·m = 25×10⁻² C·m.

The electric dipole moment is the product of one charge and the separation between the two equal and opposite charges: $p = q \times d$.

Here q = 5 C and d = 5.0 cm = 0.05 m.

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Electric dipole moment is measured in C·m.

An electric dipole consists of charges $+q$ and $-q$ separated by a distance $2a$. Its dipole moment is

$p = q \times (2a),$

i.e. charge times separation, directed from the negative to the positive charge.

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SI unit of electric dipole moment is coulomb·metre (C·m).

An electric dipole consists of charges +q and −q separated by a distance 2a. Its dipole moment is defined as:

$p = q \times 2a$

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$\vec p = q(2\vec a)$, directed from $-q$ to $+q$.

An electric dipole is a pair of equal and opposite point charges $+q$ and $-q$ separated by a small distance $2a$. The electric dipole moment is a vector quantity defined as

$\vec p = q \times 2\vec a$

where $2\vec a$ is the vector drawn from the negative charge to the positive charge, and $q$ is the magnitude of either charge.

Magnitude: $p = q(2a)$

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An electric dipole = two equal, opposite charges a small fixed distance apart, described by the dipole moment vector $\vec p$.

An electric dipole consists of two point charges of equal magnitude $q$ and opposite sign ($+q$ and $-q$), separated by a small distance $2a$. Because the net charge is zero, a dipole does not experience a net force in a uniform electric field, but it does experience a torque that tends to align it with the field.

Its strength is measured by the electric dipole moment

$\vec p = q(2\vec a)$ …