torque on coil

Question

Torque on rectangular coil (N turns, area A) carrying current I in uniform field B (coil plane at angle θ to field) is:

RankGuru · Accepted Answer

A current-carrying coil in a magnetic field experiences a torque (turning effect).
$\vec{	au} = \vec{m} 	imes \vec{B} = NI (\vec{A} 	imes \vec{B})$
- $	au = NIAB \sin 	heta$
- $	heta$ is the angle between the **magnetic moment ($NI\vec{A}$)** and the **magnetic field ($\vec{B}$)**.
- Alternatively, if $\phi$ is the angle between the plane of the coil and the field, $	heta = 90^\circ - \phi$, so $	au = NIAB \cos \phi$.

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torque on coil

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