Question 749: Electrostatics & Capacitance

Question

An electric dipole of dipole moment p is aligned parallel to a uniform electric field E. The energy required to rotate the dipole by 90
o
is

Accepted Answer

Potential energy of dipole,
$$U =  - pE\left( {\cos {	heta _2} - \cos {	heta _1}} ight)$$
Here, $${	heta _1} = {0^o},{	heta _2} = {90^o}$$
$$ 	herefore $$ U = Ã¢ÂÂ pE(cos90ÃÂ° Ã¢ÂÂ cos0ÃÂ°) = Ã¢ÂÂ pE(0 Ã¢ÂÂ 1) = pE

Answer

p
2
E

Answer

pE

Answer

infinity

Answer

pE
2

Electrostatics & Capacitance

An electric dipole of dipole moment p is aligned parallel to a uniform electric field E. The energy required to rotate the dipole by 90 o is

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