Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 583 · 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.🔍 Which is the odd one out? (a) leave the TV on standby (b) run fans in empty rooms (c) use daylight to read (d) leave fridge door open
2. 2.⚡ What does a night lamp mainly change electricity into? (a) light (b) heat (c) sound (d) movement
3. 3.True or false: an exhaust fan mainly gives out light. (a) False (b) True
4. 4.🔺 A 4.8 V supply is joined across a 120 Ω resistor. What current flows (in milliamperes, mA)?
5. 5.Which of these is the process? (a) a button press (b) compare with a limit (c) a motion sensor signal (d) a temperature reading
6. 6.🔍 Which is the odd one out? (a) keep drinks far away (b) use small battery cells (c) fly a kite near wires (d) stop if a part gets hot
7. 7.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) cell (b) voltmeter (c) wire (d) capacitor
8. 8.Which of these mainly makes movement? (a) a rice cooker (b) an electric kettle (c) a tube light (d) an exhaust fan
9. 9.🔺 A current of 25 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
10. 10.🔢 To get a sensor reading onto a phone, which is the FIRST step? (a) the cloud stores it (b) the sensor measures (c) it is sent by Wi-Fi (d) the board reads it
11. 11.🌈 Which band is read first on a resistor? (a) the one nearest an end (b) the widest gap (c) the gold band (d) any band
12. 12.📏 Which unit measures voltage? (a) volt (V) (b) ohm (Ω) (c) ampere (A) (d) watt (W)
13. 13.🔋 3 identical 1.2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
14. 14.🧩 Which part changes electrical energy into movement? (a) a motor (b) a fuse (c) an LED (d) a resistor
15. 15.Which of these is a good habit? (a) share the Wi-Fi key (b) keep factory passwords (c) change default passwords (d) share camera links
16. 16.🗺️ In an input → process → output plan, is “a motion sensor signal” the input, the process or the output? (a) process (b) output (c) input
17. 17.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) only one (c) none (d) it does not matter
18. 18.🔌 Most metals are good … (a) magnets only (b) batteries (c) insulators (d) conductors
19. 19.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) quick and clear for all (c) symbols are heavier (d) to hide the circuit
20. 20.🔌 A gap of dry air between two wires acts as … (a) a switch that is ON (b) a cell (c) an insulator (d) a conductor
21. 21.True or false: a tilt switch springs back when let go. (a) True (b) False
22. 22.🔍 Which is the odd one out? (a) a wooden stick (b) a steel spoon (c) a glass marble (d) a plastic straw
23. 23.Which of these is the process? (a) a temperature reading (b) a buzzer beeps (c) check if temp > 30 (d) an LED lights up
24. 24.🔗 Series or parallel circuit: “a break stops every bulb”? (a) series (b) parallel
25. 25.Which of these is the output? (a) a temperature reading (b) check if temp > 30 (c) a buzzer beeps (d) compare with a limit
26. 26.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
27. 27.🔍 Which is the odd one out? (a) keep factory passwords (b) cover unused cameras (c) share the Wi-Fi key (d) tap unknown app links
28. 28.🔋 8 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
29. 29.Which of these saves electricity? (a) leave fridge door open (b) switch off empty rooms (c) leave the TV on standby (d) use old filament bulbs
30. 30.⚡ What do we call a flow of electric charge through a wire? (a) a magnet (b) friction (c) sound (d) electric current
31. 31.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) smaller (d) bigger
32. 32.⚡ A 6 W device works on 12 V. What current does it take (in amperes)? =
33. 33.Which of these is a good habit? (a) tap unknown app links (b) keep factory passwords (c) read app permissions (d) ignore update messages
34. 34.⚡ A device works on 9 V and takes 1 A. What is its power (in watts)? =
35. 35.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
36. 36.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
37. 37.True or false: to open a phone charger is safe. (a) True (b) False
38. 38.🔦 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
39. 39.🔘 Two switches are in series. When does the bulb glow? (a) when both are ON (b) when either is ON (c) never (d) when both are OFF
40. 40.🧩 Which component senses how hot it is? (a) LDR (b) LED (c) resistor (d) thermistor

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