Electronics Worksheet: Simple Circuit – Open and Closed

Electronics lesson 4: Open and closed circuits · Set 682 · 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 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
3. 3.🔦 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 copper wire. Does the bulb glow? (a) No (b) Yes
4. 4.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
5. 5.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
6. 6.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) the loop is complete (d) the switch is OFF
7. 7.Which of these means the circuit is closed? (a) a wire has come loose (b) the bulb is unscrewed (c) the switch is OFF (d) all wires are joined
8. 8.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
9. 9.True or false: if the switch is OFF, the circuit is closed and current flows. (a) False (b) True
10. 10.🔦 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) No (b) Yes
11. 11.Which of these means the circuit is open? (a) a wire is cut (b) all wires are joined (c) the loop is complete (d) the switch is ON
12. 12.🔁 What do we call a circuit with a break in it? (a) an open circuit (b) a full circuit (c) a series circuit (d) a closed circuit
13. 13.True or false: if the switch is ON, the circuit is closed and current flows. (a) False (b) True
14. 14.Which of these means the circuit is open? (a) the loop is complete (b) the bulb is unscrewed (c) all wires are joined (d) the switch is ON
15. 15.🔁 Is the circuit closed or open if the bulb is unscrewed? (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. Does the bulb glow? (a) Yes (b) No
17. 17.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
18. 18.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) False (b) True
19. 19.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the switch (b) the glass (c) the base (d) the filament
20. 20.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
21. 21.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
22. 22.🔁 What must there be for a current to flow? (a) a plastic gap (b) a broken path (c) a complete loop (d) one loose end
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 ceramic cup. Does the bulb glow? (a) No (b) Yes
24. 24.True or false: if all wires are joined, the circuit is closed and current flows. (a) True (b) False
25. 25.Which of these means the circuit is closed? (a) the switch is OFF (b) the bulb is unscrewed (c) a wire has come loose (d) the switch is ON
26. 26.True or false: if a wire is cut, the circuit is closed and current flows. (a) True (b) False
27. 27.🔦 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 steel spoon. Does the bulb glow? (a) Yes (b) No
28. 28.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) none (c) only one (d) it does not matter
29. 29.Which of these means the circuit is closed? (a) a cell is taken out (b) the loop is complete (c) the bulb is unscrewed (d) a wire has come loose
30. 30.🔦 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) 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 graphite rod. Does the bulb glow? (a) No (b) Yes
32. 32.🔦 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
33. 33.🔦 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
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 plastic ruler. Does the bulb glow? (a) Yes (b) No
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 wooden stick. Does the bulb glow? (a) No (b) Yes
36. 36.Which of these means the circuit is open? (a) a wire has come loose (b) all wires are joined (c) the switch is ON (d) the loop is complete
37. 37.True or false: if a cell is taken out, the circuit is closed and current flows. (a) True (b) False
38. 38.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
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) No (b) Yes
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 steel spoon. Does the bulb glow? (a) Yes (b) No

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