**Q1. When Wheatstone bridge is in balance condition, the current through galvanometer will be**

- Maximum
- Minimum
- Zero
- Depends upon the type of galvanometer.

**Q2. Three resistors of 4 Ω, 12 Ω, and 6 Ω are connected in parallel. No. of 12 Ω resistors required to be connected in parallel to reduce the total resistance to half of its original is**

- 2
- 3
- 6
- 12

**Q3. There are n cells in a circuit. Each cell is of emf 1.5 V and has internal resistance of 0.5 Ω. When they are connected in series with a resistance of 20 Ω, they send a current of 0.6 A through the circuit. What is the value of n?**

- 5
- 10
- 15
- 20

**Q4. A circuit has 5 A current flowing through it. When an additional resistance of 2 Ω is inserted in the circuit, the current through it drops to 4 Ω. What is the initial resistance of the circuit?**

- 4 Ω
- 2 Ω
- 8 Ω
- 16 Ω

Q5. Ohm’s law states that

- V = I/R
- V = R/I
- V = IR
- V = I
^{2}R

**Q6. The type of materials whose resistivity is affected on adding the impurity is known as**

- Conductor
- Insulator
- Semiconductor
- Iron alloys

**Q7. The current in a coil of resistance 90 ohms is to be reduced by 90 percent. What value of resistance should be connected in parallel with it?**

- 9 Ω
- 100 Ω
- 90 Ω
- 10 Ω

**Q8. Copper is not used as potentiometer wire because**

- Copper is soft and flexible
- Copper has high temperature coefficient of resistance and small resistivity
- Copper has high resistivity
- Copper has low temperature coefficient of resistance

**Q9. Which of the following is an ohmic conductor?**

- diode
- LED
- Thyristor
- Metal conductor

**Q10. Three equal resistors each of resistance r are connected to form a triangle. The equivalent resistance across any two corners of the triangle is**

- 2r
- r/3
- 2r/3
- 3r

**Q11. Wheatstone bridge is used to measure**

- emf
- potential
- resistance
- current

**Q12. Two cells of 1.25 V and 0.75 V are connected in parallel. The effective voltage will be**

- 0.75 V
- 1.25 V
- 2.00 V
- 0.5 V

**Q13. A resistance of 2 Ω is connected a across the gap of a metre-bridge (the length of the wire is 100 cm) and an unknown resistance,**

*x > 2 Ω, is connected across the other gap. The balance point is noticed at l cm from the positive end of the battery. When these resistances are interchanged, the balance point shifts by 20 cm. Neglecting any correction, the unknown resistance is:*

- 3 Ω
- 4 Ω
- 5 Ω
- 6 Ω

**Q14. What is the maximum current that can be drawn from a cell of emf E and internal resistance r connected to an external resistance R?**

- I = E/r
- I = E/R
- I = E/(R+r)
- infinite

**Q15. Two identical cells are connected in series and then in parallel. When connected it series they send a current of 10 A through a 5 Ω resistor and when connected in parallel they send a current of 8 A. What is the internal resistance of each cell?**

- 2.5 Ω
- 5 Ω
- 7.5 Ω
- 10 Ω

**Q16. 1 ohm is equal to**

- 1 ampere per volt
- 1 volt per ampere
- 1 milliampere per volt
- 1 ampere per millivolt

**Q17. Three identical cells, each of 2V and internal resistance of 0.2 ohm are connected in series to an external resistance of 7.4 ohm. The current in the circuit will be**

- 0.75 A
- 1.05 A
- 2 A
- 3 A

**Q18. When the position of cell and galvanometer in a Wheatstone bridge is inter-changed, its balanced condition**

- Changes
- Remains unchanged
- Changes and it depends on cell position only
- Changes and depends on galvanometer position only

**Q19. The total resistance of three parallel resistors is**

- R
_{T}= 1/R_{1}+ 1/R_{2}+ 1/R_{3} - R
_{T}= R_{1}+ R_{2}+ R_{3} - 1/R
_{T}= 1/R_{1}+ 1/R_{2}+ 1/R_{3} - 1/R
_{T}= R_{1}+ R_{2}+ R_{3}

**Q20. While traversing a loop we must consider**

- resistors and sources of emf
- only resistors
- only sources of emf
- none of the above

**Q21. If a wire of resistivity ρ is stretched to double its length. Then its new resistivity will be**

- half of the original resistivity
- Four times the original resistivity
- Double the original resistivity
- Remains same

**Q22. Three identical cells, each of 4 V and internal resistance r, are connected in series to a 6 ohm resistor. If the current flowing in the circuit is 2 A. The internal resistance of each cell is**

- 0.11 ohm
- 0 ohm
- 0. 12 ohm
- 1.1 ohm

**Q23. If a wire of resistivity ρ is stretched to double its length. Then its new resistivity will be**

- half of the original resistivity
- Four times the original resistivity
- Double the original resistivity
- Remains same

**Q24. The resistance of a wire is r ohms. It is stretched to double its length. The new resistance of the wire in ohms is**

- r/2
- 2r
- r/4
- 4r

**Q25. Mobility of charge carriers in a conductor is given by**

- drift velocity/ electric field
- (drift velocity)(electric field)
- ( charge of an electron).drift velocity/ electric field
- mass of an electron.(drift velocity/ electric field)

**Q26. An electric bulb is rated 220 V and 100 W. Power consumed by it operated on 110 V is**

- 25 W
- 50 W
- 75 W
- 90 W

**Q27. In a potentiometer a cell of e.m.f 2V gives a balance point at 30cm. If the cell is replaced by another cell and the balance point shifts to 60cm.What is the e.m.f of the other cell?**

- 0.4 V
- 4.0 V
- 40.0 V
- 0.04 V

**Q28. The negative sign in calculations involving circuit problem signifies**

- Wrong result
- Nothing
- Current is in a direction opposite to the assumed direction
- Use of wrong factor

**Q29. Under what condition, the current drawn from the cell is maximum?**

- R = 0
- R = r
- R > r
- R < r

**Q30. The resistance of hot tungsten filament is about 10 times to that of cold tungsten filament. What will be the resistance of 100 W and 220 V lamp when not in use?**

- 484 ohm
- 4.84 ohm
- 4840 ohm
- 48.4 ohm

**Q31. Sensitivity of potentiometer can be increased by**

- Increasing the length of potentiometer wire and reducing current.
- Increasing voltage
- Decreasing length of potentiometer wire
- Increasing current in circuit

**Q32. When numbers of cells in series combination are increased, the current of the circuit will**

- Decrease
- Increase
- Remain same
- Depends on the resistance of the circuit

**Q33. The internal resistance of dry cells is ________than the common electrolytic cells.**

- lower
- higher
- equal to
- lower or equal

**Q34. Which statement is true about the conventional flow of current?**

- It flows from positive to negative because protons move inside the battery from positive to the negative terminal.
- It flows from positive to negative terminal, because electrons move from negative to positive terminal inside a battery.
- It flows from negative to positive because protons move from negative to positive terminal inside the battery.
- It flows from negative to positive because the electrons move from negative to positive terminal inside the battery.

**Q35. Meter Bridge or Slide Wire Bridge is a practical form of**

- Potentiometer
- Voltmeter
- Ammeter
- Wheatstone bridge

**Q36. Kirchhoff’s second law is applicable only to**

- Open loops
- Closed and open loops
- Closed loops
- Mechanical systems

**Q37. When number of cells in series combination is increased, the voltage of the circuit will**

- Decrease
- Increase
- Remain same
- Depends on the internal resistance of the battery

**Q38. In a metre bridge experiment null point is obtained at 20 cm from one end of the wire when resistance X is balanced against abother resistance Y. If X < Y, then where will be new position of the null point from the same end, if one decides to balance a resistance of 4X against Y**

- 50 cm
- 80 cm
- 40 cm
- 70 cm

**Q39. If the internal resistance of a cell is 20 ohm and resistance of the circuit is also 20 ohm. Will the current remain same whether the given n identical cells are in series or in parallel?**

- Can’t predict
- None of the above
- yes
- No

**Q40. Current provided by a battery is maximum when**

- internal resistance is equal to external resistance
- internal resistance is greater then external resistance
- internal resistance is less than external resistance
- none of these