Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 335 · 40 questions

Remember (Find the topic, use the idea): Find the topic: circuit, safety, formula, component, program, sensor or IoT. Use that lesson’s rule — complete loop, V = I × R, P = V × I, last command wins, true → if part. Safety answers are always: low voltage, dry hands, an adult, never the mains.

1. 1.🔁 What do we call a circuit with a break in it? (a) a full circuit (b) a series circuit (c) an open circuit (d) a closed circuit
2. 2.Which of these mainly makes movement? (a) an electric toy car (b) a torch (c) a rice cooker (d) an electric iron
3. 3.Which job needs a buzzer? (a) beep an alarm (b) show the temperature (c) spin a robot’s wheels (d) open a gate to 90°
4. 4.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
5. 5.🔦 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
6. 6.What does the microcontroller do? (a) measures the real world (b) carries the data (c) stores data online (d) reads values, decides
7. 7.🔍 Which is the odd one out? (a) a Wi-Fi smart plug (b) a smart energy meter (c) a paper calendar (d) a fitness band with app
8. 8.True or false: to use a cable with cuts is safe. (a) True (b) False
9. 9.🧩 Which component limits the current? (a) fuse (b) resistor (c) LED (d) thermistor
10. 10.📏 How many milliamperes (mA) is 0.39 A?
11. 11.💡 A battery lights 3 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
12. 12.True or false: a toggle switch flips up or down. (a) True (b) False
13. 13.True or false: energy used each second is measured in ohms (Ω). (a) True (b) False
14. 14.True or false: a small empty box is the symbol for a wire. (a) False (b) True
15. 15.📏 In the water-pipe picture of a circuit, current is like … (a) the pipe colour (b) the water pressure (c) the flow of water (d) a narrow pipe
16. 16.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) True (b) False
17. 17.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
18. 18.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 ampere (c) 1 watt (d) 1 kilowatt-hour (kWh)
19. 19.Which of these wastes electricity? (a) use LED lamps (b) run fans in empty rooms (c) close the fridge quickly (d) switch off empty rooms
20. 20.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 100 ms }
    How many milliseconds does one blink (ON + OFF) take?
21. 21.💡 2 identical bulbs are joined in parallel across a 12 V battery (ideal wires). How many volts does each bulb get? =
22. 22.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 100 (c) 1000 (d) 10
23. 23.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is ON, B is ON and C is OFF. Does the bulb glow? (a) Yes (b) No
24. 24.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) No (b) Yes
25. 25.💡 What does LED stand for? (a) light energy dial (b) low energy device (c) light-emitting diode (d) large electric dial
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 steel spoon. Does the bulb glow? (a) Yes (b) No
27. 27.⚠️ Is it safe to take cells out after use? (a) safe (b) not safe
28. 28.🔁 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
29. 29.🔍 Which is the odd one out? (a) a steel spoon (b) a rubber band (c) a steel coin (d) aluminium foil
30. 30.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
    The temperature is 36 °C. What is shown? (a) Warm (b) Cool (c) Hot
31. 31.True or false: a fuse smooths a wobbly supply. (a) True (b) False
32. 32.⚠️ Is it safe to fly kites in open fields? (a) not safe (b) safe
33. 33.🔍 Which is the odd one out? (a) a dry cork (b) a graphite rod (c) a wooden stick (d) a cotton thread
34. 34.🧮 An 8 V battery is joined to 3 Ω and 5 Ω resistors in series. What current flows (in amperes)? =
35. 35.🔍 Which is the odd one out? (a) decide if soil is dry (b) a temperature reading (c) a soil moisture reading (d) a motion sensor signal
36. 36.🌈 In the resistor colour code, which number does yellow stand for?
37. 37.⚡ Power tells us … (a) the colour of light (b) the length of a wire (c) the size of a cell (d) energy used each second
38. 38.Which of these gives us electricity? (a) a television (b) a refrigerator (c) a battery (d) a computer
39. 39.Which of these is a good habit? (a) ignore update messages (b) post your live location (c) reuse one password (d) set up with a parent
40. 40.True or false: triangle against a bar is the symbol for an ammeter. (a) True (b) False

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