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Question
Write the formula for torque acting on rotating current carrying coil in terms of magnetic dipole moment, in vector form.
Solution
The formula for torque acting on the rotating current-carrying coil is:
τ = N I A B sin θ
τ = M B sin θ
In vector Form,
`vectau = vec M xx vec B`
where,
N = Number of turns,
I = Current in the coil,
A = Area of cross - section of coil,
B = Magnetic field.
M = Magnetic dipole moment.
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