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In India, domestic power suppy is at 220 V, 50 hz, while in U.S.A, its 110 V, 60 hz. Give one advantage and one disadvantage of 220 V supply over 110 V supply. |
Answer» For transfer of power `(= V xx I)` at higher voltage (220 V instead of 110 V), current carried by wires is just half. Therefore, such wires need not be very thick, saving lot of transmission material and reducing the cost of transmission. This is one advantage of 220 V supply. But to design a device of particular wattage, `P = (V^(2))/(R )` as `V^(2)` is 4 times, R must be four times. If not, the dissipation or power in the form of heat will be larger on 220 V supply. This is one disadvantange of this supply. |
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