Current Electricity
 

  1. Calculate the current flowing through a wire of resistance 10 ohms when a potential difference of 5 volts is applied. Answer: I = V/R = 5/10 = 0.5 A

  2. A current of 2 A flows through a wire for 10 minutes. Calculate the amount of charge that flows through the wire. Answer: Q = It = 2600 = 1200 C

  3. A wire of resistance 20 ohms is connected in series with a wire of resistance 10 ohms. If a potential difference of 12 volts is applied across the combination, calculate the current flowing through each resistor. Answer: Total resistance R = 20+10 = 30 ohms I = V/R = 12/30 = 0.4 A Current through 20 ohm resistor = I = 0.4 A Current through 10 ohm resistor = I = 0.4 A

  4. Three resistors of 10 ohms, 20 ohms and 30 ohms are connected in parallel. Calculate the equivalent resistance of the combination. Answer: 1/R = 1/10 + 1/20 + 1/30 1/R = 6/60 R = 10 ohms

  5. A battery of 6 volts is connected to a resistor of 2 ohms. Calculate the power dissipated in the resistor. Answer: P = V^2/R = 6^2/2 = 18 W

  6. A wire of resistance 5 ohms is connected in series with a wire of resistance 15 ohms. If a potential difference of 10 volts is applied across the combination, calculate the current flowing through the circuit. Answer: Total resistance R = 5+15 = 20 ohms I = V/R = 10/20 = 0.5 A

  7. A 100 watt bulb is connected to a 220 volt supply. Calculate the resistance of the bulb. Answer: P = V^2/R R = V^2/P = 220^2/100 = 484 ohms

  8. Calculate the resistance of a wire of length 10 m and diameter 0.5 mm, if the resistivity of the material is 1.6 × 10^-8 Ωm.
  9. Calculate the resistance of a 20 cm long wire of diameter 0.1 mm, if the resistivity of the material is 1.72 × 10^-8 Ωm.
  10. A wire has a resistance of 20 Ω. What will be its resistance if its length is doubled?
  11. A wire of resistance 4 Ω is stretched to double its length. What is the new resistance of the wire?
  12. A wire of resistance 6 Ω is cut into three equal parts. What will be the resistance of each part?
  13. Three resistors of 2 Ω, 3 Ω and 6 Ω are connected in parallel. Calculate the total resistance of the circuit.
  14. Three resistors of 5 Ω, 10 Ω and 15 Ω are connected in series. Calculate the total resistance of the circuit.
  15. A 100 W bulb is connected to a 220 V supply. Calculate the current flowing through the bulb.
  16. A current of 2 A flows through a conductor of resistance 5 Ω. Calculate the potential difference across the conductor.
  17. A 12 V battery is connected to a resistor of 3 Ω. Calculate the current flowing through the circuit.
  18. Two resistors of 4 Ω and 6 Ω are connected in series. Calculate the current flowing through the circuit when a potential difference of 24 V is applied.
  19. Two resistors of 10 Ω and 20 Ω are connected in parallel. Calculate the current flowing through the circuit when a potential difference of 12 V is applied.
  20. A wire of length 4 m and diameter 0.1 cm has a resistance of 8 Ω. Calculate the resistivity of the material of the wire.
  21. A wire of length 12 m and diameter 0.2 cm has a resistance of 6 Ω. Calculate the resistivity of the material of the wire.
  22. A wire of resistance 2 Ω is connected to a battery of potential difference 12 V. Calculate the current flowing through the circuit.
  23. A wire of resistance 4 Ω is connected to a battery of potential difference 16 V. Calculate the current flowing through the circuit.
  24. A wire of resistance 3 Ω is connected to a battery of potential difference 9 V. Calculate the current flowing through the circuit.
  25. A 6 V battery is connected to a 3 Ω resistor and a 6 Ω resistor in series. Calculate the current flowing through the circuit.
  26. A wire of length 10 m and resistance 20 Ω is cut into two equal parts. What will be the resistance of each part?
  27. A wire of length 12 m and resistance 24 Ω is cut into three equal parts. What will be the resistance of each part?
  28. Two resistors of 2 Ω and 4 Ω are connected in series. Calculate the current flowing through the circuit when a potential difference of 6 V is applied.
  29. Two resistors of 5 Ω and 10 Ω are connected in parallel. Calculate the current flowing through the circuit when a potential difference of 12 V is applied.
  30. A wire of length 4 m and diameter 0.4 mm has a resistance of 20 Ω. Calculate the resistivity of the material of the wire.
  31. A wire of length 6 m and diameter 0.3 mm has a resistance of 8 Ω. Calculate the resistivity of the material of the wire.
  32. Two resistors of 5 Ω and 15 Ω are connected in series. Calculate the total resistance of the circuit.
  33. Two resistors of 8 Ω and 12 Ω are connected in parallel. Calculate the total resistance of the circuit.
  34. A 50 Ω resistor and a 100 Ω resistor are connected in parallel. Calculate the equivalent resistance of the circuit.
  35. A 10 Ω resistor and a 20 Ω resistor are connected in series. Calculate the equivalent resistance of the circuit.
  36. A wire of resistance 4 Ω is cut into four equal parts. What will be the resistance of each part?
  37. A wire of resistance 6 Ω is cut into six equal parts. What will be the resistance of each part?
  38. A wire of resistance 8 Ω is cut into eight equal parts. What will be the resistance of each part?
  39. Three resistors of 10 Ω, 20 Ω, and 30 Ω are connected in series. Calculate the total resistance of the circuit.
  40. Three resistors of 5 Ω, 10 Ω, and 20 Ω are connected in parallel. Calculate the total resistance of the circuit.
  41. A wire of length 4 m and diameter 0.1 mm has a resistance of 4 Ω. Calculate the resistivity of the material of the wire.
  42. A wire of length 6 m and diameter 0.2 mm has a resistance of 6 Ω. Calculate the resistivity of the material of the wire.
  43. A wire of length 8 m and diameter 0.3 mm has a resistance of 8 Ω. Calculate the resistivity of the material of the wire.
  44. A 10 V battery is connected to a 5 Ω resistor and a 10 Ω resistor in parallel. Calculate the current flowing through the circuit.
  45. A 12 V battery is connected to a 4 Ω resistor and a 8 Ω resistor in series. Calculate the current flowing through the circuit.
  46. A wire of length 8 m and resistance 24 Ω is cut into four equal parts. What will be the resistance of each part?
  47. A wire of length 6 m and resistance 12 Ω is cut into three equal parts. What will be the resistance of each part?
  48. A wire of length 10 m and resistance 40 Ω is cut into five equal parts. What will be the resistance of each part?
  49. A 60 Ω resistor and a 120 Ω resistor are connected in series. Calculate the equivalent resistance of the circuit.
  50. A 30 Ω resistor and a 60 Ω resistor are connected in parallel. Calculate the equivalent resistance of the circuit.
  51. A wire of length 8 m and diameter 0.4 mm has a resistance of 10 Ω. Calculate the resistivity of the material of the wire.
  52. A wire of length 12 m and diameter 0.3 mm has a resistance of 12 Ω. Calculate the resistivity of the material of the wire.