Jan 02, 2003 · Power is measured in watts. Current is measured in amps. Watts = volts x amps. At the bulb, 4 bulbs at 20 watts each, dissipate 80 watts, and draw 6.7 amps of current, but at the transformer, measured on the 120 volt side, the current is only 0.67 amps and the power is still 80 watts, plus a little extra for the transformer losses.
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