Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 797 · 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.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
   set pin 7 HIGH
   set pin 7 LOW
   set pin 8 LOW
   set pin 8 HIGH
   set pin 8 LOW
   Is the LED ON or OFF at the end? (a) OFF (b) ON
2. 2.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
3. 3.⏱️ How many milliseconds are in 1 second? (a) 1000 (b) 10 (c) 60 (d) 100
4. 4.Which of these is an IoT device? (a) a battery torch (b) a plain wall switch (c) a paper calendar (d) a fitness band with app
5. 5.🔺 A current of 10 mA flows when 2.2 V is joined across a resistor. What is its resistance (in ohms)?
6. 6.📏 How many kilowatts (kW) is 4000 W? =
7. 7.🔍 Which is the odd one out? (a) keep drinks far away (b) touch a switch when wet (c) fly kites in open fields (d) build with an adult near
8. 8.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) dotted circles (c) straight lines (d) wavy lines
9. 9.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a plastic straw. Does the bulb glow? (a) No (b) Yes
10. 10.🌐 Is an app-controlled bulb an IoT device? (a) not an IoT device (b) an IoT device
11. 11.⚠️ Who should be with you when you build a circuit? (a) a stranger online (b) a trusted adult (c) nobody (d) a younger child
12. 12.🔋 A 6 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
13. 13.🔋 8 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)? =
14. 14.True or false: a circle with A inside is the symbol for an ammeter. (a) True (b) False
15. 15.True or false: “how loud a sound is” is a digital signal. (a) True (b) False
16. 16.🔘 Which kind of switch closes near a magnet? (a) a tilt switch (b) a toggle switch (c) a reed switch (d) a push button
17. 17.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 24) { show “Warm” } else { show “Cool” }
    The temperature is 10 °C. What is shown? (a) Cool (b) Warm (c) Hot
18. 18.📏 Voltmeter or ammeter: which one is joined in series? (a) ammeter (b) voltmeter
19. 19.Which of these is safe? (a) keep drinks far away (b) use a cable with cuts (c) use mains for a project (d) touch a fallen wire
20. 20.⏱️ A program says “wait 1000 ms”. How many seconds is that? =
21. 21.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
22. 22.Which of these is an IoT device? (a) a battery torch (b) an app-controlled bulb (c) a plain table fan (d) a plain wall switch
23. 23.True or false: energy used each second is measured in amperes (A). (a) True (b) False
24. 24.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 HIGH
    set pin 8 HIGH
    set pin 8 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
25. 25.🔁 x = 5
    repeat 3 times { x = x × 2 }
    What is x at the end?
26. 26.💡 What happens if an LED is put in backwards? (a) it does not light (b) it lights brighter (c) it makes a sound (d) it changes colour
27. 27.True or false: to climb an electric pole is not safe. (a) False (b) True
28. 28.True or false: a push button closes near a magnet. (a) True (b) False
29. 29.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) never (c) when both are OFF (d) when both are ON
30. 30.🧮 A 22 Ω resistor is joined in series with two equal 50 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
31. 31.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) when either is ON (b) never (c) only when both are ON (d) only when both are OFF
32. 32.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = V × I (c) P = I ÷ V (d) P = V + I
33. 33.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the base (b) the glass (c) the switch (d) the filament
34. 34.⚡ What do we call a flow of electric charge through a wire? (a) sound (b) friction (c) electric current (d) a magnet
35. 35.📶 On a 5 V board, a pin set HIGH gives about … (a) 50 V (b) 5 V (c) 0 V (d) 230 V
36. 36.⚡ 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
37. 37.🔺 In the V-I-R triangle, how do we find R? (a) R = I ÷ V (b) R = V ÷ I (c) R = V + I (d) R = V × I
38. 38.Which of these usually has a microcontroller inside? (a) a microwave oven (b) a plain wall switch (c) a hand pump (d) a spinning top
39. 39.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) True (b) False
40. 40.🔘 A bulb and a cell are joined through 6 switches on 6 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?

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