Question 523: Electrostats & Capacitance

Question

Two identical electric point dipoles have dipole moments $${\overrightarrow p _1} = p\widehat i$$ and $${\overrightarrow p _2} =  - p\widehat i$$ and are held on the x
axis at distance '$$a$$' from each other. When released, they move along the x-axis with the direction
of their dipole moments remaining unchanged. If the mass of each dipole is 'm', their speed when
they are infinitely far apart is :

Accepted Answer

Using energy conservation :
KE
i
+ PE
i
= KE
f
+ PE
f
0 + $${{2KP} \over {{a^3}}} 	imes P$$ = $${1 \over 2}m{v^2} 	imes 2 + 0$$
$$ \Rightarrow $$ v = $$\sqrt {{{2{P^2}} \over {4\pi {\varepsilon _0}{a^3}m}}} $$
= $${P \over a}\sqrt {{1 \over {2\pi {\varepsilon _0}am}}} $$

Answer

$${p \over a}\sqrt {{3 \over {2\pi { \in _0}ma}}} $$

Answer

$${p \over a}\sqrt {{1 \over {\pi { \in _0}ma}}} $$

Answer

$${p \over a}\sqrt {{1 \over {2\pi { \in _0}ma}}} $$

Answer

$${p \over a}\sqrt {{2 \over {\pi { \in _0}ma}}} $$

Electrostats & Capacitance

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