Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 598 · 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.⏱️ loop forever { LED ON; wait 600 ms; LED OFF; wait 700 ms }
   How many milliseconds does one blink (ON + OFF) take?
2. 2.🧭 Which part of a microcontroller board shows the board is on? (a) the power LED (b) the reset button (c) the pins (d) the voltage regulator
3. 3.💡 Why is house wiring done in parallel? (a) so all go off together (b) each gets full voltage (c) to save copper only (d) to make bulbs dim
4. 4.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) mute it when not in use (b) put it in the bathroom (c) tell it your passwords (d) let strangers use it
5. 5.✏️ In a circuit diagram, which part is drawn as two or more cell symbols? (a) battery (b) wire (c) junction (d) motor
6. 6.📶 Digital or analog: how loud a sound is? (a) digital (b) analog
7. 7.🔁 count = 2
   while (count < 18) { count = count + 2 }
   How many times does the loop run?
8. 8.⚠️ Is it safe to use a cable with cuts? (a) not safe (b) safe
9. 9.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the if part (b) the else part (c) neither part (d) both parts
10. 10.🔍 Which is the odd one out? (a) a wind-up clock (b) a smart energy meter (c) a Wi-Fi weather station (d) an app-controlled bulb
11. 11.True or false: a plain rectangle is the symbol for a resistor. (a) True (b) False
12. 12.True or false: a washing machine has no microcontroller inside. (a) False (b) True
13. 13.⏱️ repeat 4 times { buzzer ON; wait 400 ms; buzzer OFF; wait 300 ms }
    How many milliseconds does this take in all?
14. 14.Which of these is the output? (a) a temperature reading (b) an LED lights up (c) decide if soil is dry (d) a soil moisture reading
15. 15.True or false: to keep drinks far away is safe. (a) False (b) True
16. 16.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 25 % (c) 5 % (d) 50 %
17. 17.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is ON and B is OFF. Does the bulb glow? (a) No (b) Yes
18. 18.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I × R (c) V = R ÷ I (d) V = I ÷ R
19. 19.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a push button (c) a slide switch (d) a reed switch
20. 20.🔌 Is a steel coin a conductor or an insulator? (a) an insulator (b) a conductor
21. 21.🔗 Series or parallel circuit: “a single current path”? (a) parallel (b) series
22. 22.💡 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
23. 23.🔋 How many 1.2 V cells must be joined in series to give 7.2 V?
24. 24.🧮 Adding another resistor in series makes the total resistance … (a) stay the same (b) smaller (c) zero (d) bigger
25. 25.True or false: a transistor boosts a small signal. (a) False (b) True
26. 26.What does a tilt switch do? (a) slides side to side (b) springs back when let go (c) closes when tipped over (d) flips up or down
27. 27.📏 How many ohms (Ω) is 3.4 kΩ?
28. 28.⚠️ Is it safe to touch a switch when wet? (a) not safe (b) safe
29. 29.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) No (b) Yes
30. 30.True or false: on a cell, “usually the red wire” means the + (positive) end. (a) True (b) False
31. 31.Which drawing is the symbol for a wire? (a) a long and a short line (b) a circle with a cross (c) a dot where wires meet (d) a straight line
32. 32.Which of these uses electricity? (a) a generator (b) a battery (c) a refrigerator (d) a bicycle dynamo
33. 33.🔺 A current of 2 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
34. 34.True or false: a push button works only while pressed. (a) True (b) False
35. 35.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) symbols are heavier (c) quick and clear for all (d) to hide the circuit
36. 36.True or false: a toggle switch slides side to side. (a) False (b) True
37. 37.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
38. 38.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
39. 39.True or false: a thermistor smooths a wobbly supply. (a) False (b) True
40. 40.🔘 Which kind of switch works only while pressed? (a) a toggle switch (b) a tilt switch (c) a push button (d) a reed switch

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