← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 69 · 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.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
  2. 2.Which of these means the circuit is open? (a) the switch is ON (b) the bulb is unscrewed (c) all wires are joined (d) the loop is complete
  3. 3.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) it does not matter (b) both of them (c) none (d) only one
  4. 4.Which of these means the circuit is open? (a) all wires are joined (b) a wire is cut (c) the loop is complete (d) the switch is ON
  5. 5.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
  6. 6.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the switch (c) the base (d) the glass
  7. 7.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
  8. 8.Which of these means the circuit is closed? (a) a cell is taken out (b) the switch is ON (c) a wire is cut (d) the switch is OFF
  9. 9.True or false: if the switch is OFF, the circuit is closed and current flows. (a) False (b) True
  10. 10.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
  11. 11.🔦 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
  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 steel spoon. Does the bulb glow? (a) No (b) Yes
  13. 13.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
  14. 14.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) all wires are joined (c) the switch is OFF (d) a wire has come loose
  15. 15.True or false: if the bulb is unscrewed, the circuit is closed and 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. Does the bulb glow? (a) Yes (b) No
  17. 17.🔦 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 steel spoon. Does the bulb glow? (a) Yes (b) No
  18. 18.🔦 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 woollen thread. Does the bulb glow? (a) Yes (b) No
  19. 19.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
  20. 20.True or false: if a wire has come loose, the circuit is open and no current flows. (a) False (b) True
  21. 21.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) open (b) closed
  22. 22.🔦 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 ceramic cup. Does the bulb glow? (a) No (b) Yes
  23. 23.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
  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 graphite rod. Does the bulb glow? (a) No (b) Yes
  25. 25.🔦 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 an iron nail. Does the bulb glow? (a) Yes (b) No
  26. 26.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
  27. 27.🔁 What must there be for a current to flow? (a) one loose end (b) a plastic gap (c) a broken path (d) a complete loop
  28. 28.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
  29. 29.🔦 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
  30. 30.🔦 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 spoon. Does the bulb glow? (a) Yes (b) No
  31. 31.🔦 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 copper wire. Does the bulb glow? (a) No (b) Yes
  32. 32.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
  33. 33.🔦 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
  34. 34.🔦 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 an iron nail. Does the bulb glow? (a) No (b) Yes
  35. 35.True or false: if a wire has come loose, the circuit is closed and current flows. (a) False (b) True
  36. 36.🔦 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 aluminium foil. Does the bulb glow? (a) No (b) Yes
  37. 37.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
  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 dry cork. Does the bulb glow? (a) No (b) Yes
  39. 39.True or false: if a cell is taken out, the circuit is open and no current flows. (a) True (b) False
  40. 40.🔦 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 glass marble. Does the bulb glow? (a) No (b) Yes

Answer key

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

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