Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 53 · 40 questions

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.

1. 1.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
2. 2.🔁 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
3. 3.Which of these means the circuit is open? (a) the loop is complete (b) a cell is taken out (c) all wires are joined (d) the switch is ON
4. 4.🔦 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 an iron nail. Does the bulb glow? (a) No (b) Yes
5. 5.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
6. 6.Which of these means the circuit is open? (a) all wires are joined (b) the switch is OFF (c) the loop is complete (d) the switch is ON
7. 7.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
8. 8.Which of these means the circuit is closed? (a) a wire has come loose (b) the switch is OFF (c) all wires are joined (d) a cell is taken out
9. 9.True or false: if a cell is taken out, the circuit is closed and current flows. (a) False (b) True
10. 10.🔦 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 rubber band. Does the bulb glow? (a) No (b) Yes
11. 11.🔦 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
12. 12.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
13. 13.🔦 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 glass marble. Does the bulb glow? (a) No (b) Yes
14. 14.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
15. 15.🔦 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
16. 16.Which of these means the circuit is open? (a) a wire is cut (b) the switch is ON (c) the loop is complete (d) all wires are joined
17. 17.🔁 What do we call a circuit with a break in it? (a) a series circuit (b) a closed circuit (c) a full circuit (d) an open circuit
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 safety pin. Does the bulb glow? (a) Yes (b) No
19. 19.🔦 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) No (b) Yes
20. 20.True or false: if the switch is ON, the circuit is open and no current flows. (a) True (b) False
21. 21.🔦 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 cotton thread. Does the bulb glow? (a) No (b) Yes
22. 22.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
23. 23.True or false: if a cell is taken out, the circuit is open and no current flows. (a) True (b) False
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. Does the bulb glow? (a) Yes (b) No
25. 25.True or false: if the bulb is unscrewed, 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. A gap in one wire is bridged by a paper strip. Does the bulb glow? (a) No (b) Yes
27. 27.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
28. 28.True or false: if a wire is cut, the circuit is closed and current flows. (a) False (b) True
29. 29.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) the switch is ON (c) the switch is OFF (d) a cell is taken out
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 brass key. Does the bulb glow? (a) Yes (b) No
31. 31.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
32. 32.🔦 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
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.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) closed (b) open
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 dry cork. Does the bulb glow? (a) No (b) Yes
36. 36.True or false: if the switch is OFF, the circuit is open and no current flows. (a) True (b) False
37. 37.🔦 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 band. Does the bulb glow? (a) Yes (b) No
38. 38.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
39. 39.🔦 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
40. 40.Which of these means the circuit is closed? (a) a wire has come loose (b) a wire is cut (c) the switch is OFF (d) the loop is complete

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