Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 801 · 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.True or false: a microcontroller has a built-in keyboard. (a) False (b) True
2. 2.🔍 Which is the odd one out? (a) a night lamp (b) an electric iron (c) a tube light (d) a torch
3. 3.True or false: “how bright a room is” is a digital signal. (a) True (b) False
4. 4.Which of these is an insulator? (a) a metal paper clip (b) a dry cork (c) a safety pin (d) a steel coin
5. 5.Which of these mainly gives out heat? (a) a street light (b) a night lamp (c) a buzzer (d) a rice cooker
6. 6.⚠️ Is it safe to take cells out after use? (a) not safe (b) safe
7. 7.🔺 A current of 0.5 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
8. 8.🔁 repeat 2 times { repeat 2 times { beep } }
   How many beeps are there?
9. 9.⚠️ Is it safe to open a phone charger? (a) safe (b) not safe
10. 10.True or false: “own switch for each bulb” is true of a series circuit. (a) False (b) True
11. 11.🤖 if (distance < 15) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 19 cm. What happens? (a) buzzer beeps (b) buzzer is silent
12. 12.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 240 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
13. 13.🔁 repeat 5 times { repeat 4 times { beep } }
    How many beeps are there?
14. 14.Which job needs a gas sensor? (a) warn of a gas leak (b) switch on lamps at dusk (c) water a dry plant (d) stop a robot near walls
15. 15.🧩 Which part changes electrical energy into sound? (a) a diode (b) a resistor (c) a capacitor (d) a buzzer
16. 16.🧩 Which component limits the current? (a) buzzer (b) resistor (c) LDR (d) potentiometer
17. 17.True or false: “used in house wiring” is true of a series circuit. (a) False (b) True
18. 18.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) motor (b) battery (c) voltmeter (d) switch
19. 19.🤖 Does a spinning top usually have a microcontroller inside? (a) No (b) Yes
20. 20.Which of these is not safe? (a) build with an adult near (b) keep drinks far away (c) dry your hands first (d) use a cable with cuts
21. 21.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 10 (b) 1024 (c) 1000 (d) 100
22. 22.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
23. 23.🔋 A 9 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
24. 24.⚡ What does a torch mainly change electricity into? (a) heat (b) light (c) sound (d) movement
25. 25.💡 Why is house wiring done in parallel? (a) each gets full voltage (b) so all go off together (c) to make bulbs dim (d) to save copper only
26. 26.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 7 minutes?
27. 27.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 10 seconds?
28. 28.💡 An LED is joined to a 5 V battery through a 220 Ω resistor; its long leg goes to the − side and its short leg to the + side. What happens? (a) may burn out (b) lights up (c) does not light
29. 29.🔺 A 10 V supply is joined across a 250 Ω resistor. What current flows (in milliamperes, mA)?
30. 30.🔺 A 10 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =
31. 31.Which of these is an input? (a) an LED (b) a buzzer (c) a push button (d) a motor
32. 32.🌈 In the resistor colour code, which number does yellow stand for?
33. 33.Which of these is true of a parallel circuit? (a) a single current path (b) one bulb out, all go out (c) a break stops every bulb (d) one out, the rest glow
34. 34.🔺 A current of 10 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
35. 35.🔌 Which metal is used for most electric wires at home? (a) rubber (b) glass (c) plastic (d) copper
36. 36.⚠️ Who should be with you when you build a circuit? (a) a stranger online (b) a trusted adult (c) a younger child (d) nobody
37. 37.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
    The temperature is 12 °C. What is shown? (a) Warm (b) Cool (c) Hot
38. 38.True or false: a line lifted at a gap is the symbol for a switch. (a) False (b) True
39. 39.🤖 Does a digital thermometer usually have a microcontroller inside? (a) Yes (b) No
40. 40.🔋 2 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =

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