Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 659 · 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.📏 How many ohms (Ω) is 4.3 kΩ?
2. 2.True or false: “many values in a range” is a digital signal. (a) False (b) True
3. 3.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a cotton thread across the gap. Does the bulb glow? (a) Yes (b) No
4. 4.True or false: a potentiometer smooths a wobbly supply. (a) False (b) True
5. 5.True or false: a glass marble is an insulator. (a) True (b) False
6. 6.True or false: a siren mainly makes sound. (a) True (b) False
7. 7.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
   set pin 7 HIGH
   set pin 7 LOW
   set pin 7 HIGH
   set pin 7 HIGH
   set pin 8 LOW
   Is the LED ON or OFF at the end? (a) OFF (b) ON
8. 8.🤖 “if (A AND B)” is true when … (a) both are false (b) only B is true (c) only A is true (d) both A and B are true
9. 9.True or false: “the pump turns on” is the output. (a) False (b) True
10. 10.🔍 Which is the odd one out? (a) an electric drill (b) a room heater (c) an exhaust fan (d) a mixer grinder
11. 11.🤖 Does a spinning top usually have a microcontroller inside? (a) Yes (b) No
12. 12.True or false: a bicycle bell has no microcontroller inside. (a) True (b) False
13. 13.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) True (b) False
14. 14.🔺 A current of 2.5 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
15. 15.What does a transistor do? (a) beeps for an alarm (b) boosts a small signal (c) glows using little power (d) limits the current
16. 16.💡 3 identical bulbs are joined in series with a 7.5 V battery (ideal wires). How many volts does each bulb get? =
17. 17.Which of these is true of a parallel circuit? (a) a break stops every bulb (b) one bulb out, all go out (c) bulbs share the voltage (d) used in house wiring
18. 18.🧮 Resistors of 50 Ω and 470 Ω are joined in series. What is the total resistance (in ohms)?
19. 19.🔐 Which is the strongest password for a home smart camera? (a) admin (b) 123456 (c) Tiger#Lamp42!Moon (d) password
20. 20.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) ON (b) OFF
21. 21.Which job needs a display? (a) turn to an exact angle (b) spin a robot’s wheels (c) move water to plants (d) show the temperature
22. 22.🔁 total = 0
    for i = 1 to 4 { total = total + i }
    What is total at the end?
23. 23.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) True (b) False
24. 24.🧮 Resistors of 50 Ω, 22 Ω and 68 Ω are joined in series. What is the total resistance (in ohms)?
25. 25.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
26. 26.🔺 A current of 0.5 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
27. 27.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they all go out (c) they keep glowing (d) they explode
28. 28.🧩 Which part changes electrical energy into movement? (a) a motor (b) a resistor (c) a fuse (d) an LED
29. 29.Which of these mainly makes sound? (a) an LED lamp (b) a torch (c) a siren (d) an electric toy car
30. 30.🔁 What does “count = count + 1” do? (a) takes 1 away (b) sets count to 1 (c) prints 1 (d) adds 1 to count
31. 31.🔌 Is a rubber band a conductor or an insulator? (a) a conductor (b) an insulator
32. 32.⚡ A 72 W device works on 24 V. What current does it take (in amperes)? =
33. 33.💡 2 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. Bulb 2 is taken out of its holder. How many bulbs glow?
34. 34.🔍 Which is the odd one out? (a) share the Wi-Fi key (b) cover unused cameras (c) read app permissions (d) share only needed data
35. 35.🔢 To plan an electronics project, which comes first: “test it and fix it” or “pick a problem to solve”? (a) pick a problem to solve (b) test it and fix it
36. 36.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 500 Ω resistor? (a) blue-green-brown (b) green-black-brown (c) green-black-red (d) green-black-black
37. 37.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a buzzer (c) a servo motor (d) a pump
38. 38.📏 How many milliamperes (mA) make 1 ampere? (a) 100 (b) 60 (c) 10 (d) 1000
39. 39.Which of these is a conductor? (a) a steel spoon (b) a ceramic cup (c) a rubber band (d) a paper strip
40. 40.Which of these mainly makes sound? (a) a night lamp (b) a doorbell (c) an LED lamp (d) a room heater

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