Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 969 · 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.🤖 Does a toy robot usually have a microcontroller inside? (a) Yes (b) No
2. 2.🌐 Each reading a sensor sends is 10 bytes. How many bytes do 100 readings take?
3. 3.Which of these has no microcontroller inside? (a) a washing machine (b) a wind-up toy (c) a microwave oven (d) a digital thermometer
4. 4.💡 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 8 LOW
   set pin 7 HIGH
   Is the LED ON or OFF at the end? (a) OFF (b) ON
5. 5.Which of these mainly makes sound? (a) a school bell (b) a night lamp (c) an exhaust fan (d) an electric toy car
6. 6.🧩 Which part changes electrical energy into sound? (a) a diode (b) a buzzer (c) a resistor (d) a capacitor
7. 7.True or false: an iron nail is a conductor. (a) True (b) False
8. 8.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
9. 9.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 100 (d) 1000
10. 10.⚡ A 0.9 W device works on 9 V. What current does it take (in amperes)? =
11. 11.🗺️ Before building a project, what should you write down first? (a) the final price (b) nothing at all (c) the box colour (d) inputs and outputs
12. 12.⚠️ Is it safe to dry your hands first? (a) safe (b) not safe
13. 13.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 49 Ω resistor? (a) white-yellow-black (b) yellow-white-black (c) yellow-white-brown (d) green-white-black
14. 14.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. How many bulbs glow?
15. 15.⏱️ loop forever { LED ON; wait 750 ms; LED OFF; wait 650 ms }
    How many milliseconds does one blink (ON + OFF) take?
16. 16.🔍 Which is the odd one out? (a) keep drinks far away (b) dry your hands first (c) touch a switch when wet (d) build with an adult near
17. 17.🔐 Is it a good or a risky habit to log out of shared phones? (a) risky habit (b) good habit
18. 18.🧾 A 500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
19. 19.🔁 What does “count = count + 1” do? (a) prints 1 (b) adds 1 to count (c) takes 1 away (d) sets count to 1
20. 20.Which of these is a conductor? (a) a wooden stick (b) a rubber band (c) a steel spoon (d) a paper strip
21. 21.🔁 count = 3
    repeat 2 times { count = count + 5 }
    What is count at the end?
22. 22.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
23. 23.🔍 Which is the odd one out? (a) an app-controlled bulb (b) a Wi-Fi doorbell camera (c) a Wi-Fi smart plug (d) a battery torch
24. 24.🧮 Two resistors in parallel give a total that is … (a) always zero (b) more than either one (c) less than either one (d) their sum
25. 25.Which job needs a buzzer? (a) turn to an exact angle (b) beep an alarm (c) move water to plants (d) open a gate to 90°
26. 26.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by aluminium foil. Does the bulb glow? (a) Yes (b) No
27. 27.🤖 if (distance < 30) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 31 cm. What happens? (a) buzzer beeps (b) buzzer is silent
28. 28.🌈 In the resistor colour code, which number does yellow stand for?
29. 29.True or false: an LDR senses how bright it is. (a) True (b) False
30. 30.Which of these is a good habit? (a) tap unknown app links (b) set a strong password (c) share the Wi-Fi key (d) reuse one password
31. 31.💡 Why is house wiring done in parallel? (a) to save copper only (b) each gets full voltage (c) so all go off together (d) to make bulbs dim
32. 32.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in parallel (b) by Wi-Fi (c) in series (d) not joined
33. 33.Which of these is a risky habit? (a) cover unused cameras (b) turn off unused gadgets (c) set up with a parent (d) post your live location
34. 34.🔌 Why are electric wires covered in plastic? (a) plastic makes current (b) plastic is an insulator (c) to make them heavy (d) plastic is a conductor
35. 35.Which of these is measured in watts (W)? (a) energy used each second (b) how much a part resists (c) current (d) the push of a cell
36. 36.🔘 A bulb and a cell are joined through 2 switches on 2 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?
37. 37.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 3.5 V supply. What current flows (in mA)?
38. 38.📶 Digital or analog: a knob turned part way? (a) digital (b) analog
39. 39.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 200 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
40. 40.True or false: to spot someone walking in, use a rain sensor. (a) True (b) False

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