question_answer 1)
Current flows through a conductor connected across a voltage source. Now the resistance of the conductor is reduced to one fourth to its initial value and connected across the same voltage source. The heating effect in the conductor will become
A)
Half done
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B)
Double done
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C)
Four times done
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D)
One fourth done
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question_answer 2)
A strip of copper and another of silicon are cooled from room temperature to 32 K. Which of the following is true regarding this?
A)
Resistance of copper strip decreases because it has positive temperature coefficient of resistance. done
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B)
Resistance of copper strip increases because it has negative temperature coefficient of resistance. done
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C)
Resistance of silicon strip decreases because it has negative temperature coefficient of resistance. done
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D)
Resistance of silicon strip increases because it has positive temperature coefficient of resistance. done
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question_answer 3)
An air conditioner is rated 260 V, 2.0 kW. The air conditioner is switched on for 10 hours each day. What is electrical energy consumed in 30 days?
A)
20 kW h done
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B)
2000 kW h done
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C)
600 kW h done
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D)
420 kW h done
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question_answer 4)
Match the column I with column II and select the correct option from the codes given.
Column I
Column II
(a) Electric current
(i) volt
(b) E.m.f.
(ii) ohm
(c) Resistance
(iii) ohm-metre
(d) Resistivity
(iv) ampere
A)
(a)-(iv), (b)-(ii), (c)-(i), (d)-(iii) done
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B)
(a)-(iii), (b)-(iv), (c)-(i), (d)-(ii) done
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C)
(a)-(iv), (b)-(i), (c)-(ii), (d)-(iii) done
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D)
(a)-(iii), (b)-(i), (c)-(ii), (d)-(iv) done
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question_answer 5)
What is the equivalent resistance between points A and B in the given circuit diagram?
A)
\[\frac{4}{3}r\] done
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B)
\[\frac{10}{3}r\] done
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C)
\[\frac{5}{3}r\] done
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D)
\[10r\] done
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question_answer 6)
Following graph was plotted between V and I values, across a wire. Which of the following statements) is/are correct regarding this?
A)
Value of ratio \[\frac{V}{l}\]when the potential difference is 0.8 V is not equal to the value of ratio \[\frac{V}{l}\]when the potential difference is 1.2 V. done
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B)
This graph illustrates the non-ohmic law. done
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C)
While plotting this graph, the temperature remains constant. done
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D)
All of these done
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question_answer 7)
In which of the following network of resistors the equivalent resistance between points A and B is highest?
A)
Network (i) done
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B)
Network (ii) done
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C)
Network (iii) done
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D)
All have equal equivalent resistance. done
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question_answer 8)
Which of the following statements about the current in given circuit is correct?
A)
Current at Q is greater than the current at R. done
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B)
Current at R is greater than the current at P. done
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C)
P has maximum current. done
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D)
R has maximum current. done
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question_answer 9)
An electric bulb rated 220 V, 60 W is working at full efficiency. Another identical bulb is connected in the same circuit having power supply of 220 V.
(i) If both the bulbs are connected in series then the total power consumption will be 60 W. (ii) If only one bulb is connected then the total power consumption will be 30 W. (iii) If the both bulbs are connected in parallel then the total power consumption will be 120 W.
Which of the above statement(s) is/are correct regarding the circuit?
A)
Only (i) and (ii) done
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B)
Only (ii) and (iii) done
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C)
Only (iii) done
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D)
Only (i) done
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question_answer 10)
How will be the reading in the ammeter A affected if another identical bulb Q is connected in parallel to P? (The voltage in the mains is maintained at a constant value.)
A)
The reading will be reduced to one-half. done
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B)
The reading will not be affected. done
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C)
The reading will be doubled. done
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D)
The reading will be increased four-fold. done
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question_answer 11)
Six equal resistances are connected between points P, Q and R as shown in the figure. The net resistance will be maximum between
A)
P and Q done
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B)
Q and R done
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C)
P and R done
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D)
Any two points. done
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question_answer 12)
Arrange the order of power dissipated in the given circuits, if the same current enters at point A in all the circuits and resistance of each resistor is R.
A)
(ii) > (iii) > (iv) > (i) done
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B)
(iii) > (ii) > (iv) > (i) done
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C)
(iv) > (iii) > (ii) > (i) done
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D)
(i) > (ii) > (iii) > (iv) done
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question_answer 13)
While carrying out an experiment, to find the equivalent resistance of two resistances connected in parallel, a student sets up the circuit as shown. The teacher checks it and tells him that his circuit has one or more of the following 'faults'.
(i) The resistors \[{{R}_{1}}\] and \[{{R}_{2}}\] have no been correctly connected in parallel
(ii) The voltmeter has not been correctly connected in the circuit
(iii) The ammeter and the key have not been correctly connected in the circuit.
Out of these three, the actual fault in hi circuit is/are
A)
Both (i) and (ii) done
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B)
Both (ii) and (iii) done
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C)
(i) only done
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D)
(ii) only done
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question_answer 14)
Direction: Observe the given circuit diagram and answer the following question.
What is the value of current shown by the ammeter?
A)
2 A done
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B)
0.4 A done
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C)
1.6 A done
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D)
5 A done
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question_answer 15)
Direction: Observe the given circuit diagram and answer the following question.
What is the potential difference across\[2\Omega ?\]
A)
2.5 V done
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B)
1 V done
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C)
1.6 V done
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D)
5 V done
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question_answer 16)
The resistors \[{{R}_{1}},{{R}_{2}},{{R}_{3}}\] and \[{{R}_{4}}\] in the given circuit are all equal in value and connected with a negligible resistance wire. Which of the following is correct relationship between the voltmeters readings \[{{V}_{1}},{{V}_{2}}\] and \[{{V}_{3}}\]
A)
\[{{V}_{1}}={{V}_{2}}={{V}_{3}}\] done
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B)
\[{{V}_{1}}={{V}_{2}}>{{V}_{3}}\] done
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C)
\[{{V}_{1}}<{{V}_{2}}<{{V}_{3}}\] done
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D)
\[{{V}_{1}}={{V}_{2}}<{{V}_{3}}\] done
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question_answer 17)
In the circuit shown here, the ammeter A reads 5 A and the voltmeter V reads 20 V. The correct value of resistance R is
A)
Exactly \[4\Omega \] done
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B)
Slightly greater than \[4\Omega \] done
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C)
Slightly less than \[4\Omega \] done
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D)
Zero done
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question_answer 18)
A ring is made of a wire having a resistance \[12\Omega .\] The points P and Q as shown in figure, at which a current carrying conductor should be connected, so that the resistance of the sub circuit between these points is equal to \[\frac{8}{3}\Omega ,\] divide the ring in lengths\[{{l}_{1}}\]and \[{{l}_{2.}}\]Then
A)
\[\frac{{{l}_{1}}}{{{l}_{2}}}=\frac{1}{4}\] done
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B)
\[\frac{{{l}_{1}}}{{{l}_{2}}}=\frac{1}{2}\] done
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C)
\[\frac{{{l}_{1}}}{{{l}_{2}}}=\frac{2}{3}\] done
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D)
\[\frac{{{l}_{1}}}{{{l}_{2}}}=\frac{3}{5}\] done
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question_answer 19)
Consider a thin square sheet of side x and thickness y made of a material of resistivity \[\rho \]. The resistance between two opposite faces, shown by the shaded areas in the figure is
A)
Directly proportional to x done
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B)
Directly proportional to y done
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C)
Independent of x done
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D)
Independent of y. done
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question_answer 20)
The plot represents the flow of current through a wire at three different time intervals. The ratio of charges flowing through the wire at different intervals is
A)
1 : 2 : 3 done
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B)
1 : 1 : 1 done
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C)
3 : 2 : 2 done
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D)
2 : 3 : 3 done
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