← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 591 · 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.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
  2. 2.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
  3. 3.🔦 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
  4. 4.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
  5. 5.🔦 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) Yes (b) No
  6. 6.True or false: if a cell is taken out, the circuit is closed and current flows. (a) False (b) True
  7. 7.True or false: if the switch is OFF, the circuit is open and no current flows. (a) False (b) True
  8. 8.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
  9. 9.🔁 What must there be for a current to flow? (a) a broken path (b) a plastic gap (c) a complete loop (d) one loose end
  10. 10.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the filament (c) the base (d) the switch
  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. A gap in one wire is bridged by a steel coin. Does the bulb glow? (a) Yes (b) No
  12. 12.🔦 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
  13. 13.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the switch is ON (d) a wire has come loose
  14. 14.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) a wire has come loose (c) all wires are joined (d) the switch is OFF
  15. 15.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
  16. 16.Which of these means the circuit is open? (a) the bulb is unscrewed (b) the loop is complete (c) the switch is ON (d) all wires are joined
  17. 17.🔦 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 plastic ruler. Does the bulb glow? (a) No (b) Yes
  18. 18.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) open (b) closed
  19. 19.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) only one (c) both of them (d) it does not matter
  20. 20.🔦 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) No (b) Yes
  21. 21.True or false: if the switch is ON, the circuit is open and no current flows. (a) True (b) False
  22. 22.🔦 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) No (b) Yes
  23. 23.True or false: if a wire has come loose, the circuit is closed and current flows. (a) False (b) True
  24. 24.🔦 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 paper strip. Does the bulb glow? (a) No (b) Yes
  25. 25.True or false: if a wire is cut, the circuit is open and no current flows. (a) False (b) True
  26. 26.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
  27. 27.🔦 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 ceramic cup. Does the bulb glow? (a) No (b) Yes
  28. 28.🔦 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 steel spoon. Does the bulb glow? (a) No (b) Yes
  29. 29.🔦 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 rubber eraser. Does the bulb glow? (a) Yes (b) No
  30. 30.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
  31. 31.True or false: if a cell is taken out, the circuit is open and no current flows. (a) False (b) True
  32. 32.True or false: if the loop is complete, the circuit is closed and current flows. (a) False (b) True
  33. 33.Which of these means the circuit is closed? (a) a wire has come loose (b) a wire is cut (c) a cell is taken out (d) the loop is complete
  34. 34.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
  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 ruler. Does the bulb glow? (a) Yes (b) No
  36. 36.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
  37. 37.Which of these means the circuit is open? (a) the switch is OFF (b) all wires are joined (c) the switch is ON (d) the loop is complete
  38. 38.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
  39. 39.🔦 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 cotton thread. Does the bulb glow? (a) Yes (b) No
  40. 40.🔦 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

Answer key

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

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