Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 361 · 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 does the sensor do? (a) acts on a command (b) shows data to you (c) carries the data (d) measures the real world
2. 2.🔍 Which is the odd one out? (a) a temperature sensor (b) a buzzer (c) a push button (d) a sound sensor
3. 3.True or false: “a break stops every bulb” is true of a series circuit. (a) True (b) False
4. 4.📶 On a 5 V board, a pin set HIGH gives about … (a) 5 V (b) 230 V (c) 0 V (d) 50 V
5. 5.True or false: a circle with A inside is the symbol for a resistor. (a) True (b) False
6. 6.⏱️ repeat 8 times { buzzer ON; wait 100 ms; buzzer OFF; wait 900 ms }
   How many milliseconds does this take in all?
7. 7.Which of these is a good habit? (a) share camera links (b) post your live location (c) set a strong password (d) ignore update messages
8. 8.🤖 if (temperature > 33) { show “Hot” } else if (temperature > 23) { show “Warm” } else { show “Cool” }
   The temperature is 44 °C. What is shown? (a) Cool (b) Hot (c) Warm
9. 9.True or false: the voltmeter measures current. (a) True (b) False
10. 10.True or false: a toggle switch flips up or down. (a) False (b) True
11. 11.⚡ Power tells us … (a) the colour of light (b) energy used each second (c) the size of a cell (d) the length of a wire
12. 12.Which of these means the circuit is open? (a) the loop is complete (b) the switch is ON (c) all wires are joined (d) a cell is taken out
13. 13.🔍 Which is the odd one out? (a) poke things in a socket (b) touch a switch when wet (c) fly kites in open fields (d) fly a kite near wires
14. 14.🧭 Which part of a microcontroller board runs the program? (a) the pins (b) the USB port (c) the power LED (d) the main chip
15. 15.💡 6 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. How many bulbs glow?
16. 16.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) junction (b) ammeter (c) capacitor (d) motor
17. 17.🔘 A bulb and a cell are joined through 4 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
18. 18.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) mute it when not in use (d) put it in the bathroom
19. 19.Which of these mainly makes movement? (a) an LED lamp (b) a siren (c) an exhaust fan (d) a buzzer
20. 20.🧭 Which part of a microcontroller board shows the board is on? (a) the pins (b) the voltage regulator (c) the power LED (d) the main chip
21. 21.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
22. 22.🔍 Which is the odd one out? (a) close the fridge quickly (b) leave fridge door open (c) use LED lamps (d) switch off empty rooms
23. 23.🔋 5 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
24. 24.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a ceramic cup across the gap. Does the bulb glow? (a) Yes (b) No
25. 25.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 8 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
26. 26.Which of these saves electricity? (a) run fans in empty rooms (b) leave the TV on standby (c) leave fridge door open (d) use LED lamps
27. 27.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) True (b) False
28. 28.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
29. 29.Which drawing is the symbol for a capacitor? (a) a circle with V inside (b) a line lifted at a gap (c) two equal parallel lines (d) a circle with M inside
30. 30.⚡ A bicycle dynamo changes which kind of energy into electricity? (a) movement energy (b) sound energy (c) light energy (d) chemical energy
31. 31.🌐 Each reading a sensor sends is 50 bytes. How many bytes do 70 readings take?
32. 32.🤖 if (temperature > 30) { fan ON } else { fan OFF }
    The temperature sensor reads 34 °C. What happens? (a) fan OFF (b) fan ON
33. 33.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) a break stops every bulb (c) one bulb out, all go out (d) one out, the rest glow
34. 34.🔐 Which is the strongest password for a home smart camera? (a) password (b) Tiger#Lamp42!Moon (c) 123456 (d) admin
35. 35.⚡ A 12 W device works on 12 V. What current does it take (in amperes)? =
36. 36.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = V ÷ I (c) R = V + I (d) R = I ÷ V
37. 37.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they all go out (c) they get dimmer (d) they keep glowing
38. 38.True or false: an LED lamp mainly makes movement. (a) True (b) False
39. 39.🧩 Which component smooths a wobbly supply? (a) potentiometer (b) capacitor (c) LED (d) fuse
40. 40.🧩 Which part changes electrical energy into movement? (a) a fuse (b) a resistor (c) an LED (d) a motor

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