Q.1. kilowatt hour is the unit of
(A) energy
(B) power
(C) torque
(D) force
Ans:- (A)
Q.2 Electron volt is a measure of
(A) charge
(B) potential difference
(C) current
(D) energy
Ans:- (D)
Q.3. To increase sensitivity of a potentiometer its
(A) area should be increased
(B) current should be increased
(C) current should be decreased
(D) length should be increased
Ans:-(D)
Q.4. The SI unit of electrical resistance is
(A) ohm
(B) farad
(C) coulomb
(D) siemen
Ans:- (A)
Q.5. The SI unit of electrical conductance is
(A) ohm
(B) siemen (S)
(C) ampere
(D) volt
Ans:- (B)
Q.6. 1 Faraday is equal to
(A) 1 ampere
(B) 96,500 coulomb
(C) 1.6 × 10¹⁹ Coulomb
(D) None of these
Ans:- (B)
Q.7. The S.I. unit of electrical conductivity (
σ) is
(A) siemen
(B) siemen/meter
(C) ohm
(D) ohm / meter
Ans:- (B)
Q.8. Electric current is
(A) a vector quantity
(B) a scalar quantity
(C) vector and scalar both
(D) none of these
Ans:- (B)
Q.9. Which of the following is not a unit of electric current
(A) ampere-second
(B) coulomb/second
(C) ampere
(D) none of these
Ans:- (A)
Q.10. When a body is charged its mass
(A) increases
(B) decreases
(C) remains same
(D) may increase or decrease
Ans:- (D)
Q.11. When electric current passes through a conductor is resistance
(A) decreases
(B) increases
(C) remains the same
(D) none of these
Ans:- (B)
Q.12. If that if the temperature is increased the resistivity of a metal
(A) increases
(B) decreases
(C) remains same
(D) none of these
Ans:- (A)
Q.13. Which of the following has highest electrical conductivity ?
(A) copper
(B) aluminium
(C) silver
(D) gold
Ans:- (C)
Q.15. Which of the following has highest resistivity ?
(A) Mercury
(B) copper
(C) nichrome
(D)none of these
Ans:- (C)
Q.16. Tungsten is used for lamp filaments because of its
(A) high resistivity
(B) low resistivity
(C) high melting point
(D) low melting point
Ans:- (C)
Q.17. The SI unit of electrical power is
(A) volt
(B) watt
(C) ampere
(D) Ohm
Ans:- (B)
Q.18. The wheatstone bridge is not suitable to measure
(A) very high resistance
(B) very low resistance
(C) both very high and very low resistances
(D) none of these
Ans:- (C)
Q.19. Wheatstone bridge is suitable for measuring resistances of
(A) very low value
(B) moderate value
(C) high value
(D) none of these
Ans:- (B)
Q.20. A wire is resistance R is pulled to double its length, its new resistances is
(A) 4R
(B) R
(C) 2R
(D) none of these
Ans:- (A)
Q.21. Kirchhoff’s first law (or current law, point rule) obeys the law of conservation of
(A) charge
(B) momentum
(C) energy
(D) mass
Ans:- (A)
Q.22. Kirchhoff’s second law (or loop law, mesh law) obeys the law of conservation of
(A) charge
(B) momentum
(C) energy
(D) mass
Ans:- (C)
Q.23. Ohm’s law does not obey for
(A) insulator
(B) semiconductor
(C) diode
(D) all of the above
Ans:- (D)
Q.24. A wire is stretched 40%. the percentage change in its resistance is
(A) 80%
(B) 96%
(C) 40%
(D) None
Ans:- (B)
Q.25. Dimensional formula of electric field(E) is
(A) [MLT⁻³A⁻¹]
(B) [MLA]
(C) [MLT²A⁻¹]
(D) None of these
Ans:- (A)
Q.26. 1 ampere is equivalent to
(A) 1C
(B) 1 coulomb-second
(C) coulomb/second
(D) none of these
Ans:- (C)
Q.27. Metals are good conductors of electricity because they have
(A) a small number of free electrons
(B) no free electron
(C) large number of free electrons
(D) none of these
Ans:- (C)
Q.28. If the temperature of an electrolyte is increased, its conductivity will
(A) decrease
(B) remains the same
(C) increases
(D) none of these
Ans:- (C)
Q.29. A wire of resistivity ρ is stretched of three times its length. what will be its new resistivity ?
(A) 3ρ
(B) 4ρ
(C) ρ (no change in resistivity)
(D) none of these
Ans:- (C)
Q.30. A current flows in a wire of resistance 5Ω having potential difference 7 volt for 20 minutes. the heat produced is
(A) 140 cal
(B) 280 cal
(C) 700 cal
(D) 2800 cal
Ans:- (D)
Q.31. When the temperature of the conductor decreases then the mobility of electron will be
(A) increase
(B) decrease
(C) remains same
(D) none of these
Ans:- (B)
Q.32. Power of electric circuit is
(A) VR
(B) V²R
(C) V²/R
(D) none of these
Ans:- (C)
Q.33. Three resistors of resistance 1 Ω each are connected to from a triangle. The resistance between any two terminals is
(A) 30 Ω
(B) 1/3 Ω
(C) 2/3 Ω
(D) 3/2 Ω
Ans:- 2/3 Ω
Q.34. Two resistors of resistances 12Ω and 6Ω are connected in parallel. the equivalent resistance is
(A) 24 Ω
(B) 12 Ω
(C) 6 Ω
(D) 4 Ω
Ans:- (D)
Q.35. These are three resistors of the same resistance. The ratio of their equivalent series resistance to their equivalent parallel resistance is
(A) 1:3
(B) 3:1
(C) 1:9
(D) 9:1
Ans:- (D)
Q.36. A copper wire of diameter 1 mm carries a current 6.28 A. the current density in the wire in A/m² is
(A) 6.28×10⁶
(B) 8×10⁶
(C) 6.28×10⁻⁶
(D) 8×10⁻⁶
Ans:- (B)
Q.37. A current flows in a wire of resistance 5Ω having potential difference 7 volt for 20 minutes. the heat produced is
(A) 140 cal
(B) 280 cal
(C) 700 cal
(D) 2800 cal
Ans:- (D)
Q.38. A cell of e.m.f. 1.5 V is connected with an ammeter of resistance 0.05 Ω. If the current in the circuit is 2.0 A, the internal resistance of the cell is
(A) 1Ω
(B) 0.9 Ω
(C) 0.8 Ω
(D) 0.7 Ω
Ans:- (D)
Q.39. The number of different combinations made out of three equal resistors taken together is
(A) two
(B) three
(C) four
(D) six
Ans:- (C)
Q.40. When the temperature of a metallic wire is increased then the product of conductivity and resistivity of that wire is
(A) increased
(B) decreased
(C) remains unchanged
(D) none of these
Ans:- (C)
Q.41. The temperature coefficient of resistivity is always negative
(A) for metals
(B) for semiconductor
(C) for insulator
(D) none of these
Ans:- (B)
Q.42. The temperature coefficient of resistivity is always positive
(A) for metals
(B) for semiconductor
(C) both A and B
(D) none of these
Ans:- (B)