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`

Answer 1

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 V_S = 24 V

Power associated with secondary P_S = 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`