Question

An electric dipole of moment $\overset{\rightarrow}{p}$ placed in a uniform electric field $\overset{\rightarrow}{E}$ has minimum potential energy when the angle between $\overset{\rightarrow}{p}$ and $\overset{\rightarrow}{E}$ is

• A. Zero
• B. $\frac{\pi}{2}$
• C. $\pi$
• D. $\frac{3\pi}{2}$

Answer 1

Answer: (A)

Zero

Answer 2

$U = - PE\cos\theta$

It has minimum value when θ = 0^o

i.e. $(U_{P}{)\cos 0^{o}}_{\min}$