Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 495 · 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 (light < 300) { lamp ON } else { lamp OFF }
   The light sensor reads 398. What happens? (a) lamp OFF (b) lamp ON
2. 2.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
3. 3.🔍 Which sensor would you use to measure classroom noise? (a) a motion sensor (b) a sound sensor (c) a gas sensor (d) a distance sensor
4. 4.🔁 total = 0
   for i = 1 to 8 { total = total + i }
   What is total at the end?
5. 5.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) series (b) parallel
6. 6.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
7. 7.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. Does bulb 2 glow? (a) No (b) Yes
8. 8.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
9. 9.🔋 4 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
10. 10.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = V + R (c) I = V × R (d) I = R ÷ V
11. 11.Which of these is true of a parallel circuit? (a) a break stops every bulb (b) used in house wiring (c) bulbs share the voltage (d) one bulb out, all go out
12. 12.🔌 Is a paper strip a conductor or an insulator? (a) an insulator (b) a conductor
13. 13.⏱️ A program says “wait 5000 ms”. How many seconds is that? =
14. 14.🤖 When the main loop of a microcontroller program ends, what happens? (a) the board breaks (b) it stops forever (c) it starts again (d) it deletes itself
15. 15.🔁 count = 9
    repeat 10 times { count = count + 9 }
    What is count at the end?
16. 16.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
17. 17.Which of these is a good habit? (a) accept every permission (b) share the Wi-Fi key (c) reuse one password (d) change default passwords
18. 18.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 5 V supply. What current flows (in mA)?
19. 19.Which of these is the input? (a) compare with a limit (b) a motion sensor signal (c) count button presses (d) the pump turns on
20. 20.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) neither line (d) both lines
21. 21.True or false: on an LED, the shorter leg is the anode (+). (a) True (b) False
22. 22.🧮 Resistors of 33 Ω, 330 Ω, 220 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
23. 23.🔍 Which is the odd one out? (a) a copper wire (b) a paper strip (c) a wooden stick (d) a rubber eraser
24. 24.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
25. 25.🔍 Which is the odd one out? (a) a Wi-Fi doorbell camera (b) a battery torch (c) an app-controlled bulb (d) a smart energy meter
26. 26.🌈 A resistor has the colour bands white, brown, brown. What is its value (in ohms)?
27. 27.🔐 Is it a good or a risky habit to turn off unused gadgets? (a) risky habit (b) good habit
28. 28.True or false: to start a fan when hot, use a motion sensor. (a) True (b) False
29. 29.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
30. 30.🔌 Is a rubber band a conductor or an insulator? (a) an insulator (b) a conductor
31. 31.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 9 minutes?
32. 32.Which of these is safe? (a) use mains for a project (b) take cells out after use (c) use a cable with cuts (d) touch a fallen wire
33. 33.🧮 Two equal 1000 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
34. 34.💡 Why does an LED need a resistor in series? (a) to store charge (b) to limit the current (c) to make it brighter (d) to change its colour
35. 35.True or false: “one out, the rest glow” is true of a parallel circuit. (a) True (b) False
36. 36.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a reed switch (c) a slide switch (d) a push button
37. 37.🔌 Is a wooden stick a conductor or an insulator? (a) an insulator (b) a conductor
38. 38.🧩 Which component makes a beeping sound? (a) capacitor (b) motor (c) buzzer (d) LED
39. 39.🔍 Which is the odd one out? (a) a pencil sharpener (b) a smart energy meter (c) a plain wall switch (d) a wind-up clock
40. 40.✏️ In a circuit diagram, which part is drawn as a circle with A inside? (a) voltmeter (b) capacitor (c) ammeter (d) LED

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