Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 998 · 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.💡 4 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 3 is taken out of its holder. How many bulbs glow?
2. 2.🔌 Most metals are good … (a) batteries (b) conductors (c) insulators (d) magnets only
3. 3.🧩 Which component senses how hot it is? (a) LED (b) resistor (c) thermistor (d) capacitor
4. 4.Which of these usually has a microcontroller inside? (a) a washing machine (b) a candle (c) a plain wall switch (d) a wind-up toy
5. 5.⚙️ Which actuator would you use to move water to plants? (a) a display (b) an LED (c) a buzzer (d) a pump
6. 6.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
7. 7.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 4 V supply. What current flows (in mA)?
8. 8.🔁 repeat 5 times { repeat 4 times { beep } }
   How many beeps are there?
9. 9.⚠️ Is it safe to fly kites in open fields? (a) not safe (b) safe
10. 10.True or false: a slide switch slides side to side. (a) False (b) True
11. 11.🌈 A resistor has the colour bands grey, brown, black. What is its value (in ohms)?
12. 12.🔍 Which is the odd one out? (a) switch off empty rooms (b) use LED lamps (c) unplug idle chargers (d) leave the TV on standby
13. 13.Which of these is not safe? (a) stay away from pylons (b) poke things in a socket (c) stop if a part gets hot (d) use small battery cells
14. 14.🧩 A capacitor in a circuit can … (a) measure heat (b) store charge briefly (c) make light (d) spin a wheel
15. 15.Which of these is an input? (a) a temperature sensor (b) a motor (c) a small display (d) a buzzer
16. 16.⚡ A device works on 3 V and takes 1 A. What is its power (in watts)? =
17. 17.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 1000 (d) 100
18. 18.True or false: a table fan mainly gives out light. (a) True (b) False
19. 19.🔐 Is it a good or a risky habit to install software updates? (a) good habit (b) risky habit
20. 20.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 440 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
21. 21.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
22. 22.🔍 Which is the odd one out? (a) a brass key (b) a rubber band (c) a rubber eraser (d) a glass marble
23. 23.🔺 A current of 2.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
24. 24.🔐 Is it a good or a risky habit to post your live location? (a) good habit (b) risky habit
25. 25.🤖 Does a TV remote usually have a microcontroller inside? (a) No (b) Yes
26. 26.🔋 5 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
27. 27.Which of these is safe? (a) poke things in a socket (b) climb an electric pole (c) keep drinks far away (d) throw cells in a fire
28. 28.Which of these is an input? (a) a motor (b) a sound sensor (c) a small display (d) an LED
29. 29.Which of these is measured in watts (W)? (a) how much a part resists (b) the flow of charge (c) the push of a cell (d) energy used each second
30. 30.🔁 count = 5
    repeat 10 times { count = count + 3 }
    What is count at the end?
31. 31.🤖 if (moisture < 50) { pump ON } else { pump OFF }
    The soil moisture sensor reads 32 %. What happens? (a) pump ON (b) pump OFF
32. 32.True or false: a dot where wires meet is the symbol for a junction. (a) True (b) False
33. 33.🔍 Which is the odd one out? (a) open a phone charger (b) fly kites in open fields (c) build with an adult near (d) stay away from pylons
34. 34.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the output (b) the battery (c) the process (d) the input
35. 35.🧭 Which part of a microcontroller board runs the program? (a) the pins (b) the reset button (c) the USB port (d) the main chip
36. 36.🔍 Which is the odd one out? (a) leave fridge door open (b) switch off empty rooms (c) close the fridge quickly (d) use daylight to read
37. 37.✏️ In a circuit diagram, which part is drawn as a circle with V inside? (a) diode (b) junction (c) battery (d) voltmeter
38. 38.🧮 Resistors of 20 Ω, 22 Ω, 50 Ω and 330 Ω are joined in series. What is the total resistance (in ohms)?
39. 39.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a woollen thread across the gap. Does the bulb glow? (a) Yes (b) No
40. 40.Which of these is true of a series circuit? (a) many paths for current (b) one out, the rest glow (c) own switch for each bulb (d) a single current path

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