← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 243 · 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 switch is OFF, the circuit is closed and current flows. (a) True (b) False
  2. 2.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
  3. 3.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
  4. 4.Which of these means the circuit is open? (a) the switch is ON (b) the loop is complete (c) a wire has come loose (d) all wires are joined
  5. 5.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
  6. 6.Which of these means the circuit is open? (a) the loop is complete (b) the switch is ON (c) all wires are joined (d) the bulb is unscrewed
  7. 7.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
  8. 8.🔦 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
  9. 9.Which of these means the circuit is closed? (a) the switch is OFF (b) the bulb is unscrewed (c) a cell is taken out (d) the switch is ON
  10. 10.🔁 What must there be for a current to flow? (a) one loose end (b) a complete loop (c) a broken path (d) a plastic gap
  11. 11.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
  12. 12.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) open (b) closed
  13. 13.Which of these means the circuit is open? (a) the switch is ON (b) a wire is cut (c) the loop is complete (d) all wires are joined
  14. 14.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) it does not matter (b) none (c) only one (d) both of them
  15. 15.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
  16. 16.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
  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.🔦 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 eraser. Does the bulb glow? (a) Yes (b) No
  19. 19.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the base (c) the switch (d) the filament
  20. 20.🔦 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
  21. 21.🔁 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
  22. 22.Which of these means the circuit is open? (a) the switch is ON (b) the loop is complete (c) a cell is taken out (d) all wires are joined
  23. 23.🔦 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
  24. 24.🔦 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
  25. 25.True or false: if a wire is cut, the circuit is closed and current flows. (a) True (b) False
  26. 26.🔦 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) Yes (b) No
  27. 27.True or false: if a cell is taken out, the circuit is closed and current flows. (a) True (b) False
  28. 28.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
  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. A gap in one wire is bridged by a copper wire. 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. A gap in one wire is bridged by aluminium foil. Does the bulb glow? (a) No (b) Yes
  31. 31.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
  32. 32.True or false: if a wire is cut, the circuit is open and no current flows. (a) True (b) False
  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 aluminium foil. Does the bulb glow? (a) No (b) Yes
  34. 34.🔦 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
  35. 35.🔦 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 straw. Does the bulb glow? (a) Yes (b) No
  36. 36.🔦 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
  37. 37.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
  38. 38.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
  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 plastic straw. Does the bulb glow? (a) No (b) Yes
  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. A gap in one wire is bridged by a glass marble. Does the bulb glow? (a) Yes (b) No

Answer key

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

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