Answer:
0.141 m
Explanation:
Using Faraday law for the magnetic generator, we have the following formula for the turning coil:
[tex]V = NA\frac{\Delta B}{\Delta t}[/tex]
where V = 65.7 V is the output voltage, N = 245 is the number of turns, A is the coil area. [tex]\Delta B / \Delta t [/tex] is the rate of change in magnetic flux, which can be calculated if we know that time it takes to rotate π/2 rad so B changes from 0.249 to 0.
[tex]\frac{\Delta B}{\Delta t} = \frac{\Delta B}{\frac{\pi/2}{84.5}} = \frac{0.249 - 0}{0.0186} = 13.4 T/s[/tex]
Therefore: [tex]V = NA 13.4[/tex]
[tex]65.7 = 245*13.4*A[/tex]
[tex]A = 65.7 / (245*13.4) = 0.02 m^2[/tex]
Since this is a square coil, we can calculate the side length:
[tex]s = \sqrt{A} = \sqrt{0.02} = 0.141 m[/tex]
