Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 930 · 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.🔦 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 ceramic cup. Does the bulb glow? (a) Yes (b) No
2. 2.True or false: if a wire has come loose, the circuit is open and no current flows. (a) True (b) False
3. 3.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
4. 4.🔦 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
5. 5.Which of these means the circuit is closed? (a) the switch is OFF (b) all wires are joined (c) a wire is cut (d) a cell is taken out
6. 6.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the filament (c) the base (d) the switch
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 closed and current flows. (a) False (b) True
9. 9.🔁 What must there be for a current to flow? (a) a plastic gap (b) a broken path (c) one loose end (d) a complete loop
10. 10.True or false: if the switch is ON, the circuit is closed and current flows. (a) False (b) True
11. 11.🔁 What do we call a circuit with a break in it? (a) a series circuit (b) a full circuit (c) an open circuit (d) a closed circuit
12. 12.🔦 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
13. 13.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
14. 14.True or false: if a wire is cut, the circuit is closed and current flows. (a) True (b) False
15. 15.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
16. 16.🔦 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 ceramic cup. Does the bulb glow? (a) Yes (b) No
17. 17.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) only one (b) both of them (c) none (d) it does not matter
18. 18.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
19. 19.Which of these means the circuit is closed? (a) the switch is OFF (b) the switch is ON (c) the bulb is unscrewed (d) a wire has come loose
20. 20.Which of these means the circuit is open? (a) the loop is complete (b) all wires are joined (c) the switch is ON (d) a wire is cut
21. 21.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
22. 22.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
23. 23.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) open (b) closed
24. 24.Which of these means the circuit is closed? (a) the switch is OFF (b) a wire is cut (c) a wire has come loose (d) the loop is complete
25. 25.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) False (b) True
26. 26.True or false: if all wires are joined, the circuit is open and no current flows. (a) False (b) True
27. 27.True or false: if a cell is taken out, the circuit is closed and current flows. (a) True (b) False
28. 28.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
29. 29.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
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 dry cork. Does the bulb glow? (a) Yes (b) No
31. 31.🔦 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
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 ceramic cup. Does the bulb glow? (a) Yes (b) No
33. 33.True or false: if the switch is OFF, the circuit is open and no current flows. (a) False (b) True
34. 34.🔦 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 woollen thread. 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 paper strip. Does the bulb glow? (a) No (b) Yes
36. 36.🔦 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
37. 37.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the switch is ON (d) a wire has come loose
38. 38.🔦 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 cotton thread. Does the bulb glow? (a) Yes (b) No
39. 39.🔦 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 spoon. 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. One wire has come loose from the cell. Does the bulb glow? (a) No (b) Yes

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