← Open and closed circuits lesson New set →

Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 378 · 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 closed? (a) the switch is OFF (b) the switch is ON (c) a cell is taken out (d) the bulb is unscrewed
  2. 2.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
  3. 3.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
  4. 4.Which of these means the circuit is closed? (a) the switch is OFF (b) a wire has come loose (c) a cell is taken out (d) the loop is complete
  5. 5.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
  6. 6.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
  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.Which of these means the circuit is closed? (a) all wires are joined (b) a wire is cut (c) a wire has come loose (d) the bulb is unscrewed
  9. 9.🔦 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
  10. 10.🔦 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) No (b) Yes
  11. 11.True or false: if a wire is cut, the circuit is closed and current flows. (a) False (b) True
  12. 12.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
  13. 13.🔦 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 wooden stick. Does the bulb glow? (a) No (b) Yes
  14. 14.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) both of them (c) it does not matter (d) only one
  15. 15.🔁 What do we call a circuit with a break in it? (a) a closed circuit (b) a full circuit (c) an open circuit (d) a series circuit
  16. 16.🔁 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
  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 open? (a) the loop is complete (b) all wires are joined (c) the switch is OFF (d) the switch is ON
  19. 19.🔦 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 safety pin. Does the bulb glow? (a) No (b) Yes
  20. 20.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the switch (b) the base (c) the filament (d) the glass
  21. 21.True or false: if a wire has come loose, the circuit is open and no current flows. (a) False (b) True
  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 woollen thread. Does the bulb glow? (a) No (b) Yes
  23. 23.🔦 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
  24. 24.🔦 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
  25. 25.🔦 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) No (b) Yes
  26. 26.🔦 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
  27. 27.Which of these means the circuit is open? (a) a wire has come loose (b) the switch is ON (c) the loop is complete (d) all wires are joined
  28. 28.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the switch is ON (d) the bulb is unscrewed
  29. 29.🔁 Is the circuit closed or open if the loop is complete? (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 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 ceramic cup. Does the bulb glow? (a) Yes (b) No
  32. 32.True or false: if the switch is OFF, the circuit is closed and 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 a copper wire. Does the bulb glow? (a) No (b) Yes
  34. 34.🔦 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 an iron nail. Does the bulb glow? (a) Yes (b) No
  35. 35.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
  36. 36.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
  37. 37.🔦 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 brass key. Does the bulb glow? (a) Yes (b) No
  38. 38.True or false: if a wire is cut, the circuit is open and no current flows. (a) True (b) False
  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 metal paper clip. Does the bulb glow? (a) No (b) Yes
  40. 40.🔦 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

Answer key

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

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