A power transmission line feeds input power at \(2300~\text{V}\) to a step down transformer with its primary windings having \(4000\) turns giving the output power at \(230~\text{V}.\) If the current in the primary of the transformer is \( 5~\text A\) and its efficiency is \(90\%,\) the output current would be:
1. \(45~\text A\)
2. \(50~\text A\)
3. \(20~\text A\)
4. \(25~\text A\)
Subtopic:  Transformer |
From NCERT
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A transformer consisting of \(300\) turns in the primary and \(150\) turns in the secondary gives output power of \(2.2~\text{kW}.\) If the current in the secondary coil is \(10~\text{A},\) then the input voltage and current in the primary coil are:
1. \(440~\text{V}~\text{and}~20~\text{A}\)
2. \(440~\text{V}~\text{and}~5~\text{A}\)
3. \(220~\text{V}~\text{and}~20~\text{A}\)
4. \(220~\text{V}~\text{and}~10~\text{A}\)

Subtopic:  Transformer |
From NCERT
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A power transmission line feeds input power at \(2300~\text{V}\) to a step-down transformer with its primary windings having \(4000\) turns. The output power is delivered at \(230 ~\text{V}\) by the transformer. If the current in the primary of the transformer is \(5~\text{A}\) and its efficiency is \(90\%,\) the output current would be:
1. \(50~\text{A}\)
2. \(45~\text{A}\)
3. \(35~\text{A}\)
4. \(25~\text{A}\)
Subtopic:  Transformer |
From NCERT
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Match List I with List II.
List I List II
\(\mathrm{(A)}\) AC generator \(\mathrm{(I)}\) detects the presence of current in the circuit
\(\mathrm{(B)}\) Galvanometer \(\mathrm{(II)}\) converts mechanical energy into electrical energy
\(\mathrm{(C)}\) Transformer \(\mathrm{(III)}\) works on the principle of resonance in AC circuits
\(\mathrm{(D)}\) Metal detector \(\mathrm{(IV)}\) changes an alternating voltage for a smaller or greater value
Choose the correct answer from the options given below:
1. \(\mathrm{(A)-(II), B-(I), (C)-(IV), (D)-(III)}\)
2. \(\mathrm{(A)-(II), B-(I), (C)-(III), (D)-(IV)}\)
3. \(\mathrm{(A)-(III), B-(IV), (C)-(II), (D)-(I)}\)
4. \(\mathrm{(A)-(III), B-(I), (C)-(II), (D)-(IV)} \)
Subtopic:  Transformer |
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From NCERT
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If the primary side of a transformer is connected with \(230~\text{V},~50~\text{Hz}~\text{AC}\) supply and the ratio of the number of turns of primary to the secondary winding is \(10:1.\) The load resistance at the secondary coil is \(46~\Omega\), then the power output of the secondary windings is:
1. \(11.5~\text{watt}\)
2. \(13~\text{watt}\)
3. \(16~\text{watt}\)
4. \(15.6~\text{watt}\)
Subtopic:  Transformer |
From NCERT
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