CURRENT ELECTRICITY: 10+2 PHYSICS MCQ ON CURRENT ELECTRICTY
Q1. Which has greater resistance ?
- (a) Voltmeter has more resistance
- (b) Millivoltmeter has more resistance
- (c) Both have same resistance
- (d) Depends on size of meter coil.
- (b) Millivoltmeter has more resistance
Q2. To reduce the range of voltmeter, its resistance is to be reduced. A voltmeter has a resistance G and range V. What resistance connected in parallel will convert it into a voltmeter of range V/n
- a) nG
- (b) (n + 1) G
- (c)(n-1) G
- (d) none of the above
- (d) none of the above
Q3. The sensitivity of a galvanometer does not depend upon
- (a) a very strong magnetic field in the permanent magnet
- (b) the current it measures
- (c) a very thin, weak suspension
- (d) a large number of turns in the coil
- (b) the current it measures
Q4. Out of the following an ideal voltmeter is
- (a) moving coil voltmeter
- (b) voltameter
- (c) an electrometer
- (d) hot wire voltmeter
- (c) an electrometer
Q5. The electric cell is a device to obtain
- (a) electric charge
- (b) electric force
- (c) electrons
- (d) electric energy from chemical energy
- (d) electric energy from chemical energy
Q6. Constantan wire is used for making standard resistance, because it has
- (a) high melting point
- (b) low specific resistance
- (c) high specific resistance
- (d) negligible temperature coefficient of resistance.
- (d) negligible temperature coefficient of resistance.
Q7. At temperature 0 K, the germanium behaves as
- (a) conductor
- (b) insulator
- (c) super-conductor
- (d) ferromagnetic
- (b) insulator
Q8. If temperature is decreased, then relaxation time of electrons in metals will
- (a) increase
- (b) decrease
- (c) fluctuate
- (d) remains constant.
- (a) increase
Q9. Consider the following two statements.
(A) Kirchoff's junction law follows from conservation of charge.
(B) Kirchoff's loop law follows from conservative nature of electric field.
- (a) Both A and B are correct
- (b) A is correct but B is wrong
- (c) B is correct but A is wrong
- (d) Both A and B are wrong.
- (b) A is correct but B is wrong
Q10. Wheatstone bridge is used to measure
- (a) potential
- (b) e.m.f.
- (c) current
- (d) resistance
- (d) resistance
Q11. Why is the Wheatstone bridge better than the other methods of measuring
resistances ?
- (a) It does not involve Ohm's law
- (b) It is based on Kirchoff's law
- (C) It has four resistor arms
- (d) It is a null method
- (d) It is a null method
Q12. Suppose in an experiment of Wheatstone's bridge, the positions of cells and galvanometer are interchanged, then balance point will
- (a) change
- (b) remain unchanged
- (c) depend on the internal resistance of cell and resistance of cell and resistance of galvanometer.
- (d) none of these.
- (b) remain unchanged
Q13. Drift velocity is due to :
- (a) Applied electric field over a given distance
- (b) Random motion of electrons
- (c) Random motion of holes
- (d) Rcombination of holes and electrons
- (a) Applied electric field over a given distance
Q14. Mobility is always............
- (a) positive
- (b) negative
- (c) both
- (d) none
- (a) positive
Q15. More is drift velocity ......will be the current
- (a) Less
- (b) More
- (c) Equal
- (d) None.
- (b) More
Q16. Resistance of a conductor depends directly upon :
- (a) Pressure
- (b) Area
- (c) length
- (d) None.
- (c) length
Q17. With the increase in area of cross-section, the resistance of the conductor
- (a) increase
- (b) decrease
- (c) remains same
- (d) increase 5 times of original value.
- (b) decrease
Q18. Resistivity of a conductor varies with temperature and
- (a) Nature of material
- (b) area
- (c) length
- (d) None
- (a) Nature of material
Q19. Resistivity for semiconductor
- (a) Decrease with rise in temperature
- (b) increase with temperature rise
- (c) no change
- (d) None
- (a) Decrease with rise in temperature
Q20. Resistance has SI unit as
- (a) ohm meter
- (b) ohm
- (c) mho
- (d) all of these
- (b) ohm
Q21. Which of the following have +ve temperature coefficient of resistivity.
- (a) Semiconductor
- (b) Metals
- (c) Alloys
- (d) Insulators
- (b) Metals
Q22. What is the nature of temperature coefficient of resistivity for conductors.
- (a) Always positive
- (b) Always negative
- (C) Can have positive value or negative value
- (d) Always zero.
- (a) Always positive
Q23. How to read colour bands on Resistors ?
- (a) Right to left
- (c) from both sides
- (b) Left to Right
- (d) All are correct.
- (b) Left to Right
Q24.The first two bands on the resistors are ..............
- (a) Two digits
- (b) Decimal Multiplier
- (c) Tolerance
- (d) All are incorrect.
- (a) Two digits
Q25. What colour is a 340 kтДж resistor with 5% tolerance resistive
- (a) Orange, Yellow and Yellow with Gold
- (b) Orange, Green and Yellow with Gold
- (c) Orange, Blue and Orange with Gold
- (d) Orange, Yellow and Green with Gold.
- (a) Orange, Yellow and Yellow with Gold
Q26.It is preferable to connect bulbs in series or in parallel ?
- (a) Series
- (b) Parallel
- (c) both
- (d) None
- (b) Parallel
Q27. Batteries are generally connected in
- (a) Series
- (b) Parallel
- (c) both
- (d) None.
- (a) Series
Q28. The combined resistance of 12тДж and 20тДж connected in series is
- (a) 61тДж
- (b) 32тДж
- (c) 18тДж
- (d) 41тДж
- (b) 32тДж
Q29. S.I. unit of electro motive force (emf) is
- (a) Coulomb
- (b) Ampere
- (c) Volt
- (d) Coulomb
- (c) Volt
Q30. Electromotive force.........potential difference
- (a) may be equal to
- (b) may be greater than
- (c) both (a) and (b)
- (d) None of these
- (c) both (a) and (b)
Q31. The potential difference depends on the..................flowing through conductor
- (a) Current
- (b) Voltage
- (c) both
- (d) None
- (a) Current
Q31. Electric current is a..... ..quantity
- (a) Scaler
- (b) Vector
- (C) Tensor
- (d) None of above
- (a) Scaler
Q32. S.I. unit of Electric current is
- (a) Coulomb
- (b) Ampere
- (c) Coulomb
- (d) Tesla
- (b) Ampere
Q33. Through a conductor electric current is thought to be a movement of
- (a) ions
- (b) orbits
- (c) Electrons
- (d) Protons
- (c) Electrons
Q34. Fill in the blank : 1 Ampere =
- (a) 3 x 10⁹ stat ampere
- (b) 3 x 10¹⁰ stat ampere
- (c) 3 x 10¹¹stat ampere
- (d) 3 x 10 stat ampere
- (a) 3 x 10⁹ stat ampere
Q35. Number of electrons passes in one second when current is 1 Ampere
- (a) 5.26 x 10¹⁸
- (b) 6.25 10²⁸
- (c) 2.96 x 10¹⁶
- (d) 8.65 x 10⁹
- (b) 6.25 10²⁸
Q36. If potential difference 'V' applied across conductor is increased to 3V, how will the drift velocity of electron change ?
- (a) Drift velocity becomes tripled
- (b) Drift velocity becomes doubled
- (c) Remains same
- (d) Drift velocity becomes four times
- (a) Drift velocity becomes tripled ; because drift velocity is proportional to potential difference
Q37. What is mobility ?
- (a) Ease of carrier drift
- (b) Ease of current flow
- (c) Ease of access to junction
- (d) Ease of movement
- (a) Ease of carrier drift
Q38. The relaxation time in conductors:
- (a) Increases with increase in temperature
- (b) Decreases with increase in temperature
- (c) It does not depend on temperature
- (d) may increase or decrease depends on nature of conductors
- (b) Decreases with increase in temperature
Q39. Internal resistance depends on
- (a) Nature of electrolyte
- (b) Nature of electrodes
- (c) Both (a) and (b)
- (d) Pressure
- (c) Both (a) and (b)
Q40. To draw maximum current from a combination of cells how should the cells be grouped ?
- (a) Series
- (b) Parallel
- (c) Mixed
- (d) Depends upon the relative value of external and internal resistance.
- (d) Depends upon the relative value of external and internal resistance
Q41. Two cells of e.m.f. 1.25 V and 0.75 V and internal resistance of 2тДж and 12тДж respectively are connected in series, Find the effective E.M.F.
- (a) 2V
- (b) 3V
- (c) 5V
- (d) 10V
- (b) 3V as effective emf is = E₁ + E₂
