The voltmeter scale is uncalibrated in part because we are missing two values: 1) the average of the peak magnetic field strengths across the surface bounded by the loops in the pickup coil, and 2) the maximum area of the loops of the pickup coil.
Given that the maximum area of the loop is 0.75m², and the maximum magnetic field strength at the location of the coil is 0.6 T, you should be able to find the value of a single tick mark on the voltmeter scale.
In your laboratory notebook write down a detailed procedure for doing so. Carry out this measurement with angular speeds of 25, 50, and 100 RPM. Are these values comparable? Do they need to be for the meter to be useful? Why or why not?
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