A step-up transformer is connected to an AC mains supply of \(220~\text V\) to operate at \(11000~\text V, 88~\text W.\) The current in the secondary circuit, ignoring the power loss in the transformer, is:
1. \(8~\text{mA}\)
2. \(4~\text{mA}\)
3. \(0.4~\text{A}\)
4. \(4~\text{A}\)
Subtopic:  Transformer |
 63%
Level 2: 60%+
NEET - 2024
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In an ideal transformer, the turns ratio is \(\frac{N_p}{N_s}=\frac{1}{2} .\) The ratio \(V_s:V_p\) is equal to (the symbols carry their usual meaning):
1. \(2:1\)
2. \(1:1\)
3. \(1:4\)
4. \(1:2\)
Subtopic:  Transformer |
 69%
Level 2: 60%+
NEET - 2024
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A \(12~\text{V},60~\text{W}\) lamp is connected to the secondary of a step-down transformer, whose primary is connected to AC mains of \(220~\text{V}\). Assuming the transformer to be ideal, what is the current in the primary winding?
1. \(0.37~\text{A}\)
2. \(0.27~\text{A}\)
3. \(2.7~\text{A}\)
4. \(3.7~\text{A}\)
Subtopic:  Transformer |
 75%
Level 2: 60%+
NEET - 2023
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A step-down transformer connected to an AC mains supply of \(220~\text{V}\) is made to operate at \(11~\text{V},\) \(44~\text{W}\) lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?
1. \(2~\text{A}\)
2. \(4~\text{A}\)
3. \(0.2~\text{A}\)
4. \(0.4~\text{A}\)
Subtopic:  Transformer |
 71%
Level 2: 60%+
NEET - 2021
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A transformer has an efficiency of \(90\%\) working on \(200~\text V\) and \(3~\text{kW}\) power supply. If the current in the secondary coil is \(6~\text A,\) the voltage across the secondary coil and the current in the primary coil, respectively, are:
1. \(300~\text V,~15~\text A\) 
2. \(450~\text V,~15~\text A\)
3. \(450~\text V,~13.5~\text A\)
4. \(600~\text V,~15~\text A\)
Subtopic:  Transformer |
 77%
Level 2: 60%+
AIPMT - 2014
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The primary coil of a transformer, when connected to a \(10~\text{V}\text-\)DC battery, draws a current of \(1~\text{mA}.\) The number of turns in the primary and secondary coils are \(50\) and \(100,\) respectively. The voltage across the secondary coil and the current drawn by the circuit in the secondary are respectively:
1. \(20~\text{V}\) and \(2.0~\text{mA}\)
2. \(10~\text{V}\) and \(0.5~\text{mA}\)
3. zero and therefore no current
4. \(20~\text{V}\) and \(0.5~\text{mA}\)
Subtopic:  Transformer |
Level 3: 35%-60%
NEET - 2013
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