← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 558 · 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) the loop is complete (b) the switch is ON (c) a wire has come loose (d) all wires are joined
  2. 2.True or false: if a cell is taken out, the circuit is open and no current flows. (a) False (b) True
  3. 3.🔁 What must there be for a current to flow? (a) a plastic gap (b) a complete loop (c) one loose end (d) a broken path
  4. 4.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
  5. 5.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
  6. 6.🔦 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) No (b) Yes
  7. 7.🔦 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
  8. 8.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) False (b) True
  9. 9.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
  10. 10.🔦 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
  11. 11.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) False (b) True
  12. 12.Which of these means the circuit is closed? (a) a cell is taken out (b) the switch is ON (c) the switch is OFF (d) a wire is cut
  13. 13.🔦 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 brass key. Does the bulb glow? (a) Yes (b) No
  14. 14.🔦 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
  15. 15.Which of these means the circuit is closed? (a) a cell is taken out (b) the bulb is unscrewed (c) the loop is complete (d) a wire has come loose
  16. 16.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
  17. 17.True or false: if a cell is taken out, the circuit is closed and current flows. (a) True (b) False
  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 steel coin. Does the bulb glow? (a) No (b) Yes
  19. 19.🔦 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 dry cork. Does the bulb glow? (a) No (b) Yes
  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 plastic straw. Does the bulb glow? (a) No (b) Yes
  21. 21.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) a cell is taken out (c) all wires are joined (d) a wire is cut
  22. 22.🔦 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) Yes (b) No
  23. 23.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
  24. 24.🔦 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 brass key. Does the bulb glow? (a) Yes (b) No
  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 a plastic ruler. Does the bulb glow? (a) Yes (b) No
  26. 26.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
  27. 27.🔦 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 safety pin. Does the bulb glow? (a) Yes (b) No
  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 graphite rod. Does the bulb glow? (a) Yes (b) No
  29. 29.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
  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 a paper strip. Does the bulb glow? (a) No (b) Yes
  31. 31.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
  32. 32.🔦 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) Yes (b) No
  33. 33.🔁 What do we call a circuit with a break in it? (a) a series circuit (b) a full circuit (c) a closed circuit (d) an open circuit
  34. 34.Which of these means the circuit is open? (a) all wires are joined (b) the switch is ON (c) a cell is taken out (d) the loop is complete
  35. 35.Which of these means the circuit is open? (a) the switch is OFF (b) the switch is ON (c) all wires are joined (d) the loop is complete
  36. 36.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
  37. 37.🔦 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
  38. 38.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the switch (c) the base (d) the glass
  39. 39.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
  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 graphite rod. Does the bulb glow? (a) Yes (b) No

Answer key

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

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