← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 404 · 40 questions
TalentJR

Remember (Follow the loop): Closed circuit = complete loop = current flows; open circuit = a break = no current. Check every part: live cell, good bulb, switch ON, all wires joined, any gap bridged by a conductor. If even one check fails, the bulb does not glow.

NameDateTime takenScore ___ / 40
  1. 1.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by an iron nail. Does the bulb glow? (a) No (b) Yes
  2. 2.🔁 What must there be for a current to flow? (a) a complete loop (b) a plastic gap (c) a broken path (d) one loose end
  3. 3.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
  4. 4.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) both of them (c) only one (d) it does not matter
  5. 5.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the filament (c) the base (d) the switch
  6. 6.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) closed (b) open
  7. 7.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a glass marble. Does the bulb glow? (a) Yes (b) No
  8. 8.Which of these means the circuit is closed? (a) a wire has come loose (b) all wires are joined (c) the switch is OFF (d) the bulb is unscrewed
  9. 9.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
  10. 10.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a rubber band. Does the bulb glow? (a) Yes (b) No
  11. 11.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. Does the bulb glow? (a) Yes (b) No
  12. 12.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
  13. 13.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) True (b) False
  14. 14.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a steel coin. Does the bulb glow? (a) Yes (b) No
  15. 15.True or false: if a wire is cut, the circuit is open and no current flows. (a) False (b) True
  16. 16.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a steel coin. Does the bulb glow? (a) Yes (b) No
  17. 17.True or false: if the switch is OFF, the circuit is closed and current flows. (a) False (b) True
  18. 18.Which of these means the circuit is closed? (a) the switch is OFF (b) a wire has come loose (c) the switch is ON (d) the bulb is unscrewed
  19. 19.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a rubber eraser. Does the bulb glow? (a) Yes (b) No
  20. 20.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) a cell is taken out (c) a wire is cut (d) the loop is complete
  21. 21.Which of these means the circuit is open? (a) all wires are joined (b) a cell is taken out (c) the switch is ON (d) the loop is complete
  22. 22.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
  23. 23.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a cotton thread. Does the bulb glow? (a) No (b) Yes
  24. 24.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
  25. 25.Which of these means the circuit is open? (a) the loop is complete (b) all wires are joined (c) the switch is ON (d) a wire is cut
  26. 26.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by an iron nail. Does the bulb glow? (a) No (b) Yes
  27. 27.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
  28. 28.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
  29. 29.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a metal paper clip. Does the bulb glow? (a) Yes (b) No
  30. 30.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a brass key. Does the bulb glow? (a) Yes (b) No
  31. 31.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
  32. 32.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
  33. 33.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
  34. 34.True or false: if a cell is taken out, the circuit is open and no current flows. (a) False (b) True
  35. 35.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. A gap in one wire is bridged by a plastic straw. Does the bulb glow? (a) Yes (b) No
  36. 36.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
  37. 37.🔁 What do we call a circuit with a break in it? (a) a full circuit (b) a series circuit (c) an open circuit (d) a closed circuit
  38. 38.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a steel spoon. Does the bulb glow? (a) No (b) Yes
  39. 39.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a wooden stick. Does the bulb glow? (a) Yes (b) No
  40. 40.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open

Answer key

  1. No
  2. a complete loop
  3. open
  4. both of them
  5. the filament
  6. open
  7. No
  8. all wires are joined
  9. False
  10. No
  11. No
  12. open
  13. True
  14. No
  15. True
  16. No
  17. False
  18. the switch is ON
  19. No
  20. the loop is complete
  21. a cell is taken out
  22. No
  23. No
  24. open
  25. a wire is cut
  26. No
  27. Yes
  28. closed
  29. Yes
  30. No
  31. False
  32. False
  33. open
  34. True
  35. No
  36. No
  37. an open circuit
  38. Yes
  39. No
  40. closed

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids