A transformer is used to light a 140 W, 24 V bulb from a 240 V a.c. ma – McqOptions

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1.	A transformer is used to light a 140 W, 24 V bulb from a 240 V a.c. mains. The current in the main cable is 0.7 A. The efficiency of the transformer is
A.	\[63.8\text{ }%\]
B.	\[83.3\text{ }%\]
C.	\[16.7%\]
D.	\[36.2%\]
Answer» C. \[16.7%\]

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