Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 561 · 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.🔐 Privacy for a smart device means controlling … (a) who can see your data (b) its battery size (c) its colour (d) how loud it beeps
2. 2.What does a buzzer do? (a) boosts a small signal (b) senses how bright it is (c) lets current go one way (d) beeps for an alarm
3. 3.🔍 Which is the odd one out? (a) an LED lamp (b) a mixer grinder (c) a street light (d) a torch
4. 4.🔺 A 3 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
5. 5.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
6. 6.🧩 Which part changes electrical energy into movement? (a) a motor (b) an LED (c) a fuse (d) a resistor
7. 7.Which drawing is the symbol for a wire? (a) triangle against a bar (b) a straight line (c) one tall, one short bar (d) a circle with A inside
8. 8.💡 3 identical bulbs are joined in parallel across a 9 V battery (ideal wires). How many volts does each bulb get? =
9. 9.🧮 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
10. 10.🌐 A weather station sends one reading every 30 seconds. How many readings does it send in 5 minutes?
11. 11.🌈 In the resistor colour code, which number does yellow stand for?
12. 12.🔺 A 6 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
13. 13.Which of these means the circuit is closed? (a) a wire is cut (b) the switch is ON (c) the switch is OFF (d) a wire has come loose
14. 14.🔘 Which kind of switch works only while pressed? (a) a slide switch (b) a reed switch (c) a push button (d) a tilt switch
15. 15.🔘 Which kind of switch slides side to side? (a) a toggle switch (b) a tilt switch (c) a slide switch (d) a push button
16. 16.🗺️ In an input → process → output plan, is “count button presses” the input, the process or the output? (a) process (b) output (c) input
17. 17.⚡ Which tiny particles drift along a metal wire to carry the current? (a) water drops (b) photons (c) dust particles (d) electrons
18. 18.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 4 minutes?
19. 19.🔺 A 15 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
20. 20.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 150 ms }
    How many times does the LED blink in 1 second?
21. 21.⚡ Which formula gives electric power? (a) P = V + I (b) P = V × I (c) P = V ÷ I (d) P = I ÷ V
22. 22.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) blinks 500 times (c) pauses for half a second (d) turns the LED off
23. 23.💡 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. Bulbs 4 and 6 are taken out of their holders. Does bulb 3 glow? (a) No (b) Yes
24. 24.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) nothing at all (d) the final price
25. 25.Which drawing is the symbol for a cell? (a) a plain rectangle (b) triangle, bar and arrows (c) a circle with V inside (d) one tall, one short bar
26. 26.🔍 Which is the odd one out? (a) a safety pin (b) a plastic ruler (c) a steel spoon (d) a brass key
27. 27.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 37 Ω resistor? (a) yellow-violet-black (b) violet-orange-black (c) orange-violet-brown (d) orange-violet-black
28. 28.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the reset button (b) the pins (c) the voltage regulator (d) the USB port
29. 29.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity
30. 30.True or false: the ammeter measures voltage. (a) True (b) False
31. 31.🔁 total = 0
    for i = 1 to 5 { total = total + i }
    What is total at the end?
32. 32.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 watt (c) 1 kilowatt-hour (kWh) (d) 1 volt
33. 33.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 530 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
34. 34.⏱️ loop forever { LED ON; wait 650 ms; LED OFF; wait 50 ms }
    How many milliseconds does one blink (ON + OFF) take?
35. 35.🔁 count = 1
    repeat 10 times { count = count + 2 }
    What is count at the end?
36. 36.🔘 What does a switch do in a circuit? (a) opens or closes the loop (b) makes electricity (c) changes the voltage (d) stores current
37. 37.🧩 Which component has coloured bands? (a) resistor (b) thermistor (c) potentiometer (d) buzzer
38. 38.Which of these is the process? (a) an alert on the phone (b) check if temp > 30 (c) a motion sensor signal (d) a buzzer beeps
39. 39.💡 In a series circuit, how many paths does the current have? (a) none (b) one (c) two (d) one for each bulb
40. 40.⚡ A device works on 9 V and takes 1 A. What is its power (in watts)? =

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