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# Rotation Direction of a Dipole in an Electric Field

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Figure 1 depicts an electric dipole aligned along the $x$ axis, in a constant electric field.

The field is given by:

$$\vec{E} = -E_0 \hat{z}$$

…where $E_0$ is a positive constant. The positive and negative charges are arranged symmetrically about the $y$ axis, each being a distance $r$ from the axis.

Figure 2 shows four possible scenarios, $A$ through $D$, describing four possible senses in which the dipole can rotate when first encountering this electric field.

Which of these four scenarios best describes the initial rotation of the dipole?

A

Scenario $A$.

B

Scenario $B$.

C

Scenario $C$.

D

Scenario $D$.