Current Electricity · JEE Main previous year questions

2023 60 questions

1. Q452023 · 13 Apr 2023 · Shift 1
   
   1. A.${\mathrm{P}}_{\mathrm{B}}<{\mathrm{P}}_{\mathrm{C}}<{\mathrm{P}}_{\mathrm{D}}<{\mathrm{P}}_{\mathrm{A}}$
   2. B.${\mathrm{P}}_{\mathrm{C}}<{\mathrm{P}}_{\mathrm{B}}<{\mathrm{P}}_{\mathrm{A}}<{\mathrm{P}}_{\mathrm{D}}$
   3. C.${\mathrm{P}}_{\mathrm{C}}<{\mathrm{P}}_{\mathrm{D}}<{\mathrm{P}}_{\mathrm{A}}<{\mathrm{P}}_{\mathrm{B}}$
   4. D.${\mathrm{P}}_{\mathrm{A}}<{\mathrm{P}}_{\mathrm{B}}<{\mathrm{P}}_{\mathrm{C}}<{\mathrm{P}}_{\mathrm{D}}$
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   Answer: B

2. Q462023 · 13 Apr 2023 · Shift 1
   
   1. A.
   2. B.
   3. C.
   4. D.
   Show answer

   Answer: D

3. Q512023 · 13 Apr 2023 · Shift 1· Numerical answer

   When a resistance of $5\Omega$ is shunted with a moving coil galvanometer, it shows a full scale deflection for a current of $250\text{ mA}$, however when $1050\Omega$ resistance is connected with it in series, it gives full scale deflection for $25\text{ volt}$. The resistance of galvanometer is __________ $\Omega$.

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   Answer: 50

4. Q542023 · 13 Apr 2023 · Shift 1· Numerical answer

   A potential ${\mathrm{V}}_0$ is applied across a uniform wire of resistance $R$. The power dissipation is $P_1$. The wire is then cut into two equal halves and a potential of $V_0$ is applied across the length of each half. The total power dissipation across two wires is $P_2$. The ratio $P_2:{\mathrm{P}}_1$ is $\sqrt{x}:1$. The value of $x$ is ___________.

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   Answer: 16

5. Q552023 · 13 Apr 2023 · Shift 1· Numerical answer
   
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   Answer: 25

6. Q572023 · 13 Apr 2023 · Shift 2· Numerical answer

   An insulated copper wire of 100 turns is wrapped around a wooden cylindrical core of the cross-sectional area $24{\text{ cm}}^2$. The two ends of the wire are connected to a resistor. The total resistance in the circuit is $12\Omega$. If an externally applied uniform magnetic field in the core along its axis changes from $1.5\text{ T}$ in one direction to $1.5\text{ T}$ in the opposite direction, the charge flowing through a point in the circuit during the change of magnetic field will be ___________ mC.

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   Answer: 60

7. Q422023 · 12 Apr 2023 · Shift 1

   A wire of resistance $160\Omega$ is melted and drawn in a wire of one-fourth of its length. The new resistance of the wire will be

   1. A.$640\Omega$
   2. B.$40\Omega$
   3. C.$16\Omega$
   4. D.$10\Omega$
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   Answer: D

8. Q372023 · 11 Apr 2023 · Shift 1
   
   1. A.NAND
   2. B.AND
   3. C.OR
   4. D.NOR
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   Answer: B

9. Q482023 · 11 Apr 2023 · Shift 1

   The current sensitivity of moving coil galvanometer is increased by $25\%$. This increase is achieved only by changing in the number of turns of coils and area of cross section of the wire while keeping the resistance of galvanometer coil constant. The percentage change in the voltage sensitivity will be:

   1. A.$+25\%$
   2. B.$-50\%$
   3. C.$-25\%$
   4. D.Zero
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   Answer: A

10. Q602023 · 11 Apr 2023 · Shift 1· Numerical answer
    
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    Answer: 1

11. Q412023 · 11 Apr 2023 · Shift 2
    
    1. A.NOR
    2. B.AND
    3. C.NAND
    4. D.OR
    Show answer

    Answer: B

12. Q592023 · 11 Apr 2023 · Shift 2· Numerical answer

    A coil has an inductance of $2\text{H}$ and resistance of $4\Omega$. A $10\text{ V}$ is applied across the coil. The energy stored in the magnetic field after the current has built up to its equilibrium value will be _________ $\times 10^{-2}\text{ J}$.

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    Answer: 625

13. Q602023 · 11 Apr 2023 · Shift 2· Numerical answer

    Two identical cells each of emf $1.5\text{ V}$ are connected in series across a $10\Omega$ resistance. An ideal voltmeter connected across $10\Omega$ resistance reads $1.5\text{ V}$. The internal resistance of each cell is _________ $\Omega$.

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    Answer: 5

14. Q312023 · 10 Apr 2023 · Shift 1

    Given below are two statements: Statement I : If the number of turns in the coil of a moving coil galvanometer is doubled then the current sensitivity becomes double. Statement II : Increasing current sensitivity of a moving coil galvanometer by only increasing the number of turns in the coil will also increase its voltage sensitivity in the same ratio In the light of the above statements, choose the correct answer from the options given below :

    1. A.Statement I is true but Statement II is false
    2. B.Statement I is false but Statement II is true
    3. C.Both Statement I and Statement II are false
    4. D.Both Statement I and Statement II are true
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    Answer: A

15. Q402023 · 10 Apr 2023 · Shift 1
    
    1. A.$16\Omega$
    2. B.$20\Omega$
    3. C.$3.2\Omega$
    4. D.$24\Omega$
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    Answer: C

16. Q522023 · 10 Apr 2023 · Shift 1· Numerical answer

    10 resistors each of resistance $10\Omega$ can be connected in such as to get maximum and minimum equivalent resistance. The ratio of maximum and minimum equivalent resistance will be __________.

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    Answer: 100

17. Q532023 · 10 Apr 2023 · Shift 1· Numerical answer
    
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    Answer: 18

18. Q322023 · 10 Apr 2023 · Shift 2
    
    1. A.$\frac{I_3}{I_4}=1$
    2. B.$\frac{I_1}{I_2}=2$
    3. C.$\frac{I_2}{I_3}=1$
    4. D.$\frac{I_1}{I_2}=1$
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    Answer: B

19. Q572023 · 10 Apr 2023 · Shift 2· Numerical answer

    A rectangular parallelopiped is measured as $1\text{ cm}\times 1\text{ cm}\times 100\text{ cm}$. If its specific resistance is $3\times 10^{-7}\Omega \text{m}$, then the resistance between its two opposite rectangular faces will be _________ $\times 10^{-7}\Omega$.

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    Answer: 3

20. Q332023 · 8 Apr 2023 · Shift 1

    Certain galvanometers have a fixed core made of non magnetic metallic material. The function of this metallic material is

    1. A.to bring the coil to rest quickly
    2. B.to produce large deflecting torque on the coil
    3. C.to oscillate the coil in magnetic field for longer period of time
    4. D.to make the magnetic field radial
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    Answer: A

21. Q452023 · 8 Apr 2023 · Shift 1
    
    1. A.
    2. B.
    3. C.
    4. D.
    Show answer

    Answer: B

22. Q482023 · 8 Apr 2023 · Shift 1
    
    1. A.$\frac{5}{4}$
    2. B.$\frac{3}{4}$
    3. C.$1$
    4. D.$\frac{4}{5}$
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    Answer: D

23. Q382023 · 8 Apr 2023 · Shift 2
    
    1. A.$30\mathrm{k\Omega }$
    2. B.$20\mathrm{k\Omega }$
    3. C.$5\mathrm{k\Omega }$
    4. D.$10\mathrm{k\Omega }$
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    Answer: C

24. Q512023 · 8 Apr 2023 · Shift 2· Numerical answer

    The number density of free electrons in copper is nearly $8\times 10^{28}{\mathrm{m}}^{-3}$. A copper wire has its area of cross section $=2\times 10^{-6}{\mathrm{m}}^2$ and is carrying a current of $3.2\mathrm{A}$. The drift speed of the electrons is ____ $\times 10^{-6}\mathrm{m}{\mathrm{s}}^{-1}$

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    Answer: 125

25. Q602023 · 8 Apr 2023 · Shift 2· Numerical answer

    A series combination of resistor of resistance $100\Omega$, inductor of inductance $1\mathrm{H}$ and capacitor of capacitance $6.25\mu \mathrm{F}$ is connected to an ac source. The quality factor of the circuit will be ____

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    Answer: 4