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Question
The output of a step-down transformer is measured to be 24 V when connected to a 12-watt light bulb. The value of the peak current is ______.
Options
`1/sqrt(2) A`
`sqrt(2) A`
2 A
`2sqrt(2) A`
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Solution
The output of a step-down transformer is measured to be 24 V when connected to a 12-watt light bulb. The value of the peak current is `underline(1/sqrt(2) A)`.
Explanation:
It decreases voltage and increases current
|
VS < VP NS < NP ES < EP iS < iP RS < RP tS < tP kS < 1 |
 |
According to the problem output/secondary voltage VS = 24 V
Power associated with secondary PS = 12 W
`I_S = P_S/V_S = 12/24` = 0.5 A
Amplitude of the current in the secondary winding
`I _O = I_S sqrt(2)`
= `(0.5)(1.414) = 0.707 = 1/sqrt(2) A`
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