Question

why in ac - dc conversion, when the switch is closed the sum of voltages around the loop is non zero​

Answer 1

Answer:

Through the use of a transformer, AC permits simple voltage changes (stepping up and down). High-voltage/low-current transmissions can reduce the problem of voltage drop (I²R loss). Because the conversion from AC to DC is also easy, AC facilitates the supply of power to DC-driven devices as well