Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 510 · 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.True or false: to water a dry plant, use a motion sensor. (a) False (b) True
2. 2.🔌 Which metal is used for most electric wires at home? (a) plastic (b) glass (c) copper (d) rubber
3. 3.🧮 Resistors of 10 Ω, 50 Ω and 470 Ω are joined in series. What is the total resistance (in ohms)?
4. 4.🔋 Does a wind turbine give electricity or use electricity? (a) gives electricity (b) uses electricity
5. 5.🔺 A current of 20 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
6. 6.🔺 A 7.5 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
7. 7.⚡ What does a school bell mainly change electricity into? (a) movement (b) light (c) sound (d) heat
8. 8.Which of these gives us electricity? (a) a television (b) a water pump (c) a solar panel (d) a computer
9. 9.🔌 Is a glass marble a conductor or an insulator? (a) a conductor (b) an insulator
10. 10.Which of these usually has a microcontroller inside? (a) a wind-up toy (b) a TV remote (c) a plain wall switch (d) a candle
11. 11.📏 How many amperes (A) is 2110 mA? =
12. 12.🌈 A resistor has the colour bands red, white, red. What is its value (in ohms)?
13. 13.🔺 A current of 0.5 A flows when 1.5 V is joined across a resistor. What is its resistance (in ohms)?
14. 14.Which of these is not safe? (a) take cells out after use (b) use small battery cells (c) use mains for a project (d) dry your hands first
15. 15.💡 A red LED uses 2 V and should get 10 mA. It runs from a 6 V supply. What resistor (in ohms) is needed in series?
16. 16.⏱️ A program says “wait 2500 ms”. How many seconds is that? =
17. 17.✏️ In a circuit diagram, which part is drawn as two or more cell symbols? (a) wire (b) switch (c) battery (d) bulb
18. 18.🤖 if (moisture < 50) { pump ON } else { pump OFF }
    The soil moisture sensor reads 36 %. What happens? (a) pump OFF (b) pump ON
19. 19.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 8 LOW
    set pin 7 HIGH
    set pin 8 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
20. 20.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
21. 21.True or false: “a single current path” is true of a parallel circuit. (a) True (b) False
22. 22.What does a buzzer do? (a) glows using little power (b) beeps for an alarm (c) limits the current (d) blows if current is high
23. 23.Which of these is a conductor? (a) a wooden stick (b) a plastic ruler (c) a rubber band (d) a copper wire
24. 24.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) capacitor (b) wire (c) cell (d) battery
25. 25.🔍 Which is the odd one out? (a) a small display (b) a speaker (c) a sound sensor (d) a motor
26. 26.⚡ What does a rice cooker mainly change electricity into? (a) light (b) movement (c) sound (d) heat
27. 27.⏱️ 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
28. 28.💡 What does LED stand for? (a) low energy device (b) large electric dial (c) light-emitting diode (d) light energy dial
29. 29.🧮 A 47 Ω resistor is joined in series with two equal 1000 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
30. 30.🔍 Which is the odd one out? (a) use small battery cells (b) dry your hands first (c) fly kites in open fields (d) poke things in a socket
31. 31.Which of these is the process? (a) an LED lights up (b) count button presses (c) a motion sensor signal (d) a buzzer beeps
32. 32.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
33. 33.⚡ A home appliance on the 230 V mains takes 0.5 A. What is its power (in watts)?
34. 34.Which of these is the input? (a) check if temp > 30 (b) a soil moisture reading (c) a buzzer beeps (d) the pump turns on
35. 35.🤖 Does a toy robot usually have a microcontroller inside? (a) No (b) Yes
36. 36.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
37. 37.📏 Which unit measures resistance? (a) volt (V) (b) watt (W) (c) ampere (A) (d) ohm (Ω)
38. 38.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
39. 39.True or false: “used in house wiring” is true of a series circuit. (a) False (b) True
40. 40.Which of these mainly makes movement? (a) a mixer grinder (b) a traffic signal (c) a torch (d) a night lamp

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