COMEDK · Physics · 23. Alternating Current
A transformer has 400 turns in its primary winding and 800 turns in its secondary winding. The primary voltage is \(20 \mathrm{~V}\) and the load in the secondary is 4 ohm. The current in the primary, assuming it to be an ideal transformer, is
- A 2 A
- B 40 A
- C 4 A
- D 20 A
Answer & Solution
Correct Answer
(D) 20 A
Step-by-step Solution
Detailed explanation
For an ideal transformer, the ratio of voltages is equal to the ratio of the number of turns: \(\dfrac{V_s}{V_p} = \dfrac{N_s}{N_p}\) Given \(N_p = 400\), \(N_s = 800\), and \(V_p = 20 \text{ V}\), we have: \(\dfrac{V_s}{20} = \dfrac{800}{400} = 2\)…
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