← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 288 · 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 a wire is cut, the circuit is closed and current flows. (a) True (b) False
  2. 2.🔦 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) No (b) Yes
  3. 3.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
  4. 4.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
  5. 5.Which of these means the circuit is open? (a) the switch is ON (b) the switch is OFF (c) all wires are joined (d) the loop is complete
  6. 6.🔁 What do we call a circuit with a break in it? (a) an open circuit (b) a full circuit (c) a closed circuit (d) a series circuit
  7. 7.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
  8. 8.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) the switch is OFF (c) the loop is complete (d) a wire is cut
  9. 9.🔦 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 graphite rod. Does the bulb glow? (a) No (b) Yes
  10. 10.🔁 Is the circuit closed or open if all wires are joined? (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 safety pin. Does the bulb glow? (a) Yes (b) No
  13. 13.🔦 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 aluminium foil. Does the bulb glow? (a) Yes (b) No
  14. 14.🔦 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 glass marble. Does the bulb glow? (a) Yes (b) No
  15. 15.🔦 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 wooden stick. Does the bulb glow? (a) Yes (b) No
  16. 16.🔦 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 aluminium foil. Does the bulb glow? (a) No (b) Yes
  17. 17.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
  18. 18.Which of these means the circuit is closed? (a) all wires are joined (b) a wire is cut (c) the bulb is unscrewed (d) a wire has come loose
  19. 19.🔦 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
  20. 20.🔦 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 dry cork. Does the bulb glow? (a) Yes (b) No
  21. 21.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the switch (c) the glass (d) the base
  22. 22.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
  23. 23.🔦 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 paper strip. Does the bulb glow? (a) No (b) Yes
  24. 24.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
  25. 25.True or false: if the switch is OFF, the circuit is open and no current flows. (a) False (b) True
  26. 26.🔦 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
  27. 27.Which of these means the circuit is open? (a) all wires are joined (b) the switch is ON (c) the loop is complete (d) a cell is taken out
  28. 28.Which of these means the circuit is open? (a) the switch is ON (b) a wire has come loose (c) all wires are joined (d) the loop is complete
  29. 29.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
  30. 30.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
  31. 31.🔁 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
  32. 32.True or false: if the switch is ON, the circuit is closed and current flows. (a) False (b) True
  33. 33.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
  34. 34.🔦 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 graphite rod. Does the bulb glow? (a) No (b) Yes
  35. 35.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
  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 a ceramic cup. Does the bulb glow? (a) Yes (b) No
  37. 37.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
  38. 38.🔦 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
  39. 39.🔦 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 woollen 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 OFF. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No

Answer key

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

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