COMEDK · Physics · 23. Alternating Current
A transformer which steps down \(330 \mathrm{~V}\) to \(33 \mathrm{~V}\) is to operate a device having impedance \(110 \Omega\). The current drawn by the primary coil of the transformer is :
- A 3 A
- B 0.03 A
- C 1.5 A
- D 0.3 A
Answer & Solution
Correct Answer
(B) 0.03 A
Step-by-step Solution
Detailed explanation
The secondary voltage \(V_s\) is \(33 \text{ V}\) and the impedance of the device connected to the secondary coil is \(Z = 110 \Omega\). The current in the secondary coil \(I_s\) is given by Ohm's law: \(I_s = \dfrac{V_s}{Z} = \dfrac{33}{110} = 0.3 \text{ A}\) For an ideal…
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