Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 653 · 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.Which of these means the circuit is open? (a) the switch is ON (b) the loop is complete (c) all wires are joined (d) the switch is OFF
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 metal paper clip. Does the bulb glow? (a) Yes (b) No
3. 3.🔁 What must there be for a current to flow? (a) a broken path (b) one loose end (c) a plastic gap (d) a complete loop
4. 4.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
5. 5.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the base (c) the switch (d) the glass
6. 6.🔁 What do we call a circuit with a break in it? (a) a full circuit (b) an open circuit (c) a closed circuit (d) a series circuit
7. 7.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
8. 8.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) the loop is complete (c) a wire is cut (d) the switch is OFF
9. 9.🔦 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
10. 10.Which of these means the circuit is open? (a) all wires are joined (b) the switch is ON (c) a wire is cut (d) the loop is complete
11. 11.🔦 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
12. 12.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
13. 13.Which of these means the circuit is closed? (a) the switch is OFF (b) a cell is taken out (c) all wires are joined (d) the bulb is unscrewed
14. 14.True or false: if a wire has come loose, the circuit is closed and current flows. (a) False (b) True
15. 15.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
16. 16.🔦 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
17. 17.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
18. 18.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) only one (b) none (c) both of them (d) it does not matter
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 aluminium foil. Does the bulb glow? (a) Yes (b) No
20. 20.True or false: if the switch is ON, the circuit is closed and current flows. (a) True (b) False
21. 21.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) open (b) closed
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 rubber eraser. Does the bulb glow? (a) Yes (b) No
23. 23.Which of these means the circuit is open? (a) the loop is complete (b) a cell is taken out (c) the switch is ON (d) all wires are joined
24. 24.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
25. 25.🔦 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) Yes (b) No
26. 26.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
27. 27.🔦 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
28. 28.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
29. 29.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
30. 30.🔦 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
31. 31.True or false: if a wire is cut, the circuit is open and no current flows. (a) True (b) False
32. 32.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
33. 33.🔦 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 copper wire. Does the bulb glow? (a) Yes (b) No
34. 34.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
35. 35.True or false: if the loop is complete, the circuit is closed and current flows. (a) False (b) True
36. 36.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
37. 37.Which of these means the circuit is closed? (a) a cell is taken out (b) a wire has come loose (c) a wire is cut (d) the switch is ON
38. 38.🔦 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) No (b) Yes
39. 39.🔦 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
40. 40.🔦 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

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