a lamp is connected to a secondary coil ( 80 turns) of a transformer by long leads which have a resistance of 2.5 ohms. Primary coil( 1600 turns voltage is 220v). the power input to the primary coil is 44w. 1) what is the voltage across the secondary coil2) what is the current across the secondary coil3) what is the electrical power dissipated in the lamp
Assuming perfect transformer. turns ratio 1600/80 20:1 secondary voltage is 220/20 11 volts primary current is 44/220 0.2 amps secondary current is 0.2 x 20 4 amps drop across wires is 4 x 2.5 10 volts. This assumes the 2.5 ohm number is for both leads, not each. voltage across lamp is 11v – 10v 1 volt power in lamp is 1 v x 4 a 4 watts. .
