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1. |
A conducting disc of conductivity a has a radius 'a' and thickness 'f. If the magnetic field B is applied in a direction perpendicular to the plane of the disc changes with time at the rate of \[\frac{dB}{dt}=\alpha \]. Calculate the power dissipated in the disc due to the induced current. |
A. | \[\frac{\pi t\sigma {{a}^{4}}}{8}{{\alpha }^{2}}\] |
B. | \[\frac{\pi t\sigma {{a}^{4}}}{4}{{\alpha }^{2}}\] |
C. | \[\frac{\pi t\sigma {{a}^{4}}}{2}{{\alpha }^{2}}\] |
D. | \[\frac{2\pi t\sigma {{a}^{4}}}{3}{{\alpha }^{2}}\] |
Answer» B. \[\frac{\pi t\sigma {{a}^{4}}}{4}{{\alpha }^{2}}\] | |