Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 236 · 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.🤖 if (distance < 10) { buzzer beeps } else { buzzer is silent }
   The distance sensor reads 16 cm. What happens? (a) buzzer beeps (b) buzzer is silent
2. 2.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
3. 3.True or false: to change default passwords is a risky habit. (a) False (b) True
4. 4.🤖 Microcontroller or laptop: which one uses very little power? (a) microcontroller (b) laptop
5. 5.🧮 A 1 V battery is joined to 3 Ω and 2 Ω resistors in series. What current flows (in amperes)? =
6. 6.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 360 Ω resistor? (a) orange-blue-brown (b) orange-blue-red (c) blue-orange-brown (d) orange-blue-black
7. 7.🔺 A current of 40 mA flows when 8.8 V is joined across a resistor. What is its resistance (in ohms)?
8. 8.What does a motor do? (a) turns a fan or wheels (b) makes a beeping sound (c) has coloured bands (d) lets current go one way
9. 9.🔍 Which is the odd one out? (a) a steel spoon (b) a paper strip (c) a rubber eraser (d) a ceramic cup
10. 10.🔺 A current of 0.1 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
11. 11.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
12. 12.True or false: to measure classroom noise, use a soil moisture sensor. (a) False (b) True
13. 13.🔌 Which part of a screwdriver should an electrician hold? (a) the metal tip (b) the steel shaft (c) the bare end (d) the plastic handle
14. 14.⚡ A cell changes stored chemical energy into which kind of energy? (a) nuclear energy (b) wind energy (c) sound energy (d) electrical energy
15. 15.True or false: a plain wall switch has no microcontroller inside. (a) False (b) True
16. 16.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) turns the LED off (c) waits 500 seconds (d) pauses for half a second
17. 17.🤖 Microcontroller or laptop: which one needs much more power? (a) microcontroller (b) laptop
18. 18.Which of these is the output? (a) a button press (b) a buzzer beeps (c) compare with a limit (d) a light level reading
19. 19.🧮 Two equal 1000 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
20. 20.⚙️ What is an actuator? (a) a battery (b) a sensor (c) a program (d) an output that acts
21. 21.Which drawing is the symbol for a wire? (a) a straight line (b) triangle against a bar (c) a line lifted at a gap (d) a circle with A inside
22. 22.🔋 How many volts does one ordinary torch cell give? (a) 15 V (b) 1.5 V (c) 0.5 V (d) 230 V
23. 23.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
24. 24.🔦 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 metal paper clip. Does the bulb glow? (a) No (b) Yes
25. 25.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
26. 26.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) voltmeter (b) resistor (c) cell (d) switch
27. 27.🔺 A current of 2 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
28. 28.💡 What happens if an LED is put in backwards? (a) it changes colour (b) it makes a sound (c) it lights brighter (d) it does not light
29. 29.🧩 Which component is a resistance knob? (a) potentiometer (b) LDR (c) resistor (d) motor
30. 30.⏱️ A program says “wait 7000 ms”. How many seconds is that? =
31. 31.🔍 Which is the odd one out? (a) a button press (b) a temperature reading (c) a buzzer beeps (d) a light level reading
32. 32.True or false: an LED lamp mainly makes movement. (a) True (b) False
33. 33.🧮 Resistors of 33 Ω, 33 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
34. 34.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a buzzer (c) a motor (d) an LED
35. 35.🔢 To get a sensor reading onto a phone, which comes first: “it is sent by Wi-Fi” or “the app shows it”? (a) the app shows it (b) it is sent by Wi-Fi
36. 36.True or false: the voltmeter measures current. (a) True (b) False
37. 37.⚡ 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
38. 38.🔐 Who should decide which smart devices go in a child’s room? (a) the app’s adverts (b) an online stranger (c) a parent or guardian (d) nobody at all
39. 39.Which drawing is the symbol for a battery? (a) a circle with A inside (b) two or more cell symbols (c) a line lifted at a gap (d) two equal parallel lines
40. 40.True or false: the flow of charge is measured in amperes (A). (a) False (b) True

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