What current does the lamp need to light normally

Reference no: EM131026890

A transformer connected to a 240 volt a.c mains is used to light a 12V/36W lamp.

a) what current does the lamp need to light normally?

b)if the efficiency of the transformer is 75%, what current is drawn from the mains?

calculate the magnitude of the ressistance of a resistor that should be connected in series with the lamp if the lamp were connected directly to the mains.

Reference no: EM131026890

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