Hello. I was studying for intro physics on topic of electromagnetism and stumbled upon one problem.(adsbygoogle = window.adsbygoogle || []).push({});

Q. A thin wire of lengh L is made of an insulating material. The wire is bent to form a circular loop, and a positive charge q is distributed uniformly around the circumference of the loop. The loop is then set into rotation with angular speed w around an axis perpendicular to the plane of the loop and passing through its center. If the loop is in a region where there is a uniform magnetic field B directed parallel to the plane of the loop, calculate the magnitude of the magnetic torque on the loop.

--> I drew the diagram and I have the equation to find the torque handy but cannot relate angular velocity w to the equation.

torque t = IBA sin a,

where I= current, B= magnetic field, A=sectional area

Also, what is the difference between a conducting loop with charge q distributed over the loop that is rotating and a stationary loop with current flowing around the loop? (similarly, I cannot figure out how to relate angular velocity w to current I)

Thanks for your immediate help and insight!

K.Kim

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# Help needed on intro physics

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