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Mention the two characteristic properties of the material suitable for making core of a transformer
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0
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7766
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September 8, 2016
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Why is the core of a transformer laminated?
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0
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1552
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September 8, 2016
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Show a plot of variation of alternating emf versus time generated by a loop of wire rotating in a magnetic field,
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0
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2784
|
September 8, 2016
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Derive an expression for the impedance of a series LCR circuit connected to an AC supply of variable frequency
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1
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12524
|
September 8, 2016
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A series LCR circuit is connected to an a.c
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1
|
4991
|
September 8, 2016
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With the help of a diagram, explain the principle and working of a device which produces current that reverses its direction after regular intervals of time
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1
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9104
|
September 8, 2016
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An a.c. source of voltage
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1
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2225
|
September 8, 2016
|
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A source of a.c. voltage
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1
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1745
|
September 8, 2016
|
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A circuit containing an 80 mH inductor and a 250 mu F capacitor in series connected to a 240 V, 100 rad/s supply
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1
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3901
|
September 8, 2016
|
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An inductor L of inductance XL is connected in series with a bulb B and an a.c. source
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1
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11018
|
September 8, 2016
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When an a.c. source is connected to an ideal inductor show that the average power supplied by the source over a complete cycle is zero
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1
|
9885
|
September 8, 2016
|
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In a series LCR circuit obtain the conditions under
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1
|
2913
|
September 8, 2016
|
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A capacitor 'C', a variable resistor 'R' and a bulb 'B' are connected in series to the ac mains in circuit s as shown
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1
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2268
|
September 8, 2016
|
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The figure shows a series LCR circuit connected to a variable frequency
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1
|
4953
|
September 8, 2016
|
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Define'Wattless current'
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0
|
2537
|
September 8, 2016
|
|
Why is choke coil needed in the use of fluorescent tubes with ac mains?
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0
|
1274
|
September 8, 2016
|
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The graphs (i) and (ii) represent the variation of the opposition
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1
|
2124
|
September 8, 2016
|
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Show that in an a.c. circuit containing a pure inductor, the voltage is ahead of current by in phase
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0
|
2417
|
September 8, 2016
|
|
An alternating voltage given by V = 140 sin 314 t is connected across a pure resistor of 50 ohm
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1
|
10623
|
September 8, 2016
|
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Show that the current leads the voltage in phase by TT/2 in an ac circuit containing an ideal capacitor
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0
|
2531
|
September 8, 2016
|
|
Define the term 'rms value of the current'. How is it related to the peak value?
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0
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7069
|
September 8, 2016
|
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State which of the two a capacitor or an inductor, tends to become SHORT when the frequency of the applied alternating voltage has a high value
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0
|
2181
|
September 8, 2016
|
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Why is the use of a.c. voltage preferred over d.c. voltage ? Give two reasons
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0
|
5722
|
September 8, 2016
|
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Plot a graph showing variation of capacitive reactance with the change in the frequency of the a.c. source
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0
|
7180
|
September 8, 2016
|
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Define capacitative reactance. Write its S.I. units
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0
|
2152
|
September 8, 2016
|
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A device 'X' is connected
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1
|
6286
|
September 8, 2016
|