Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 616 · 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 component senses how bright it is? (a) LDR (b) buzzer (c) resistor (d) fuse
2. 2.Which drawing is the symbol for an ammeter? (a) a circle with A inside (b) one tall, one short bar (c) a circle with an X in it (d) a circle with V inside
3. 3.🔢 To run one loop of a plant-watering program, which is the FIRST step? (a) switch the pump on/off (b) wait a few seconds (c) read the soil sensor (d) compare with the limit
4. 4.🧮 Two resistors in parallel give a total that is … (a) their sum (b) always zero (c) less than either one (d) more than either one
5. 5.True or false: on a cell, “the shorter symbol line” means the − (negative) end. (a) True (b) False
6. 6.🔁 count = 0
   while (count < 6) { count = count + 2 }
   How many times does the loop run?
7. 7.True or false: “a door: open or shut” is a digital signal. (a) True (b) False
8. 8.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) a single current path (c) each gets the full volts (d) one bulb out, all go out
9. 9.⚡ A 15 W device works on 5 V. What current does it take (in amperes)? =
10. 10.🔐 Why install updates on IoT devices? (a) they delete the Wi-Fi (b) they fix security holes (c) they change the colour (d) they make it heavier
11. 11.🔺 A 3.75 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
12. 12.True or false: a circle with M inside is the symbol for a bulb. (a) False (b) True
13. 13.Which of these is a conductor? (a) a rubber eraser (b) a steel spoon (c) a glass marble (d) a plastic straw
14. 14.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
15. 15.🌈 A resistor has the colour bands violet, orange, yellow. What is its value in kilo-ohms (kΩ)? =
16. 16.💡 A red LED uses 2 V and should get 25 mA. It runs from a 6 V supply. What resistor (in ohms) is needed in series?
17. 17.True or false: a glass marble is a conductor. (a) True (b) False
18. 18.📏 How many milliamperes (mA) is 2.32 A?
19. 19.🧮 A 1.5 V battery is joined to 2 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
20. 20.True or false: on a cell, “the flat end” means the + (positive) end. (a) False (b) True
21. 21.🔋 Identical cells side by side (in parallel) give … (a) no voltage (b) the same voltage (c) half the voltage (d) double the voltage
22. 22.🧮 A 22 Ω resistor is joined in series with two equal 10 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
23. 23.📏 Which unit measures how much a part resists? (a) ampere (A) (b) ohm (Ω) (c) watt (W) (d) volt (V)
24. 24.True or false: a plastic straw is a conductor. (a) False (b) True
25. 25.🧩 Which component glows using little power? (a) diode (b) LED (c) resistor (d) potentiometer
26. 26.🔁 repeat 4 times { repeat 2 times { beep } }
    How many beeps are there?
27. 27.⏱️ loop forever { LED ON; wait 350 ms; LED OFF; wait 950 ms }
    How many milliseconds does one blink (ON + OFF) take?
28. 28.💡 3 identical bulbs are joined in series with a 3 V battery (ideal wires). How many volts does each bulb get? =
29. 29.🔌 Is a temperature sensor an input or an output for a microcontroller? (a) input (b) output
30. 30.🔍 Which is the odd one out? (a) a speaker (b) a temperature sensor (c) a motor (d) a water pump
31. 31.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 5 % (c) 25 % (d) 50 %
32. 32.🤖 How does a new program get onto a microcontroller board? (a) uploaded over USB (b) sent by sound (c) typed on the chip (d) drawn with a pen
33. 33.🔁 repeat 4 times { repeat 3 times { beep } }
    How many beeps are there?
34. 34.Which of these is a good habit? (a) post your live location (b) share the Wi-Fi key (c) ignore update messages (d) change default passwords
35. 35.True or false: a digital alarm clock usually has a microcontroller inside. (a) True (b) False
36. 36.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 200 ms }
    How many milliseconds does one blink (ON + OFF) take?
37. 37.⏱️ How many milliseconds are in 1 second? (a) 100 (b) 60 (c) 10 (d) 1000
38. 38.Which of these is safe? (a) use mains for a project (b) throw cells in a fire (c) touch a switch when wet (d) take cells out after use
39. 39.Which of these is a risky habit? (a) share the Wi-Fi key (b) change default passwords (c) share only needed data (d) cover unused cameras
40. 40.🔢 To get a sensor reading onto a phone, which comes first: “the sensor measures” or “the board reads it”? (a) the board reads it (b) the sensor measures

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