(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A copper wire with cross-sectional area S=2.5 mm^2 is bent to make three sides of a square frame that can pivot about the axis 00' as shown below. The wire is located in a uniform vertical magnetic field B. If upon passing a current I=16 milliAmperes through the wire, the wire deflects by an angle Θ= 0 degrees, find value of B (in SI units).

2. Relevant equations

F = Force, measured in newtons

I = current in wire, measured in amperes

B = magnetic field vector, measured in teslas

= vector cross product

L = a vector, whose magnitude is the length of wire (measured in metres), and whose direction is along the wire, aligned with the direction of conventional current flow.

3. The attempt at a solution

I can't seem to find what r and the unit vector for r is.

Any hints? Or am I looking at this in the wrong way?

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# Homework Help: Magnetic field of a bent copper wire

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