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Bugsy23
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Homework Statement
A circular loop of wire of radius 1.5 cm is mounted in the Earth’s magnetic field, with no other magnetic fields present. It is free to rotate about an east–west horizontal axis which lies along a diameter of the coil. At what angular speed must it be rotated in order for the maximum current induced in it to be 1.0 mA? Describe the orientation of the coil relative to the Earth’s magnetic field
(i)
when the current has its maximum magnitude,
(ii)
when the current has its minimum magnitude.
Take the Earth’s magnetic field to be uniform and pointing north with a magnitude of 1.9 × 10−5 T.
Homework Equations
Vmax = imax ω L
V = iR
Vind(t)=dφ(t)/dt
φ = ABcosθ
ω=2π/T
The Attempt at a Solution
I've tried to find ways around these equations, but I keep getting stuck because there's always something missing, and it seems impossible to work it out without knowing either the period of rotation or the resistance of the coil. I can work out the magnetic flux for any given value of θ, but I can't find the rate of change of magnetic flux with respect to t since I don't have any information about t. Can anyone give me a clue if there's a way to do this?