# An electric dipole of length 4 cm, when placed with its axis making an angle of 60° with a uniform electric field, experiences a torque of 4 square root of 3 Nm. Calculate the potential energy of the dipole, if it has charge ±8 nC - Physics

An electric dipole of length 4 cm, when placed with its axis making an angle of 60° with a uniform electric field, experiences a torque of 4sqrt3Nm. Calculate the potential energy of the dipole, if it has charge ±8 nC

#### Solution

Torque, τ=PEsinθ=(Ql)Esinθ    ...(1)

Here, l is the length of the dipole, Q is the charge and E is the electric field.

Potential energy, U=PEcosθ=(Ql)Ecosθ    ...(2)

Dividing (2) by (1):

T/U=((Ql)Esintheta)/(-(Ql)Ecostheta)=-tantheta

=>U=-T/(tantheta)

=>U=-T/(tan60^@)

=>U=(-4sqrt3)/sqrt3

U=4 J

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