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In an ideal step down transformer, the i...

In an ideal step down transformer, the input voltage is 400V and the output voltage is 20 V. The output voltage is used to operate a device, having an impendance of 100 ohms. What is the current in the primary circuit?

A

10 mA

B

20 mA

C

5 mA

D

1 mA

Text Solution

Verified by Experts

The correct Answer is:
A
`I_(s) = V/Z = 20/100 = 0.2 A`
`(I_p)/(I_s) = (V_s)/(V_p) :. I_(p) = 0.2 xx 20/400 :. I_(p) = 1/100 A = 10 mA`.
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MARVEL PUBLICATION-ELECTROMAGNETIC INDUCTION AND ALTERNATING CURRENTS -TEST YOUR GRASP - 16
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