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Problem 1. The primary winding of a transformer with a toroidal core is supplied with a square wave voltage with amplitude of +50 V and a frequency of 100 kHz. Assuming a uniform flux density in the core, calculate the minimum number of primary winding turns required to keep the peak flux density in the core below 0.15 Wb/m/? if the core cross sectional area is 0635 cm*. Plot the voltage and flux density waveforms in steady state as function of time