Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 368 · 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.What does a slide switch do? (a) stays where you flip it (b) slides side to side (c) closes near a magnet (d) closes when tipped over
2. 2.⏱️ loop forever { LED ON; wait 950 ms; LED OFF; wait 400 ms }
   How many milliseconds does one blink (ON + OFF) take?
3. 3.✏️ In a circuit diagram, which part is drawn as a dot where wires meet? (a) junction (b) capacitor (c) motor (d) switch
4. 4.Which of these means the circuit is open? (a) the bulb is unscrewed (b) the switch is ON (c) all wires are joined (d) the loop is complete
5. 5.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) False (b) True
6. 6.⚠️ Who should be with you when you build a circuit? (a) a younger child (b) a stranger online (c) nobody (d) a trusted adult
7. 7.True or false: “decide if soil is dry” is the process. (a) False (b) True
8. 8.Which job is done by the pins? (a) connect sensors and LEDs (b) restarts the program (c) runs the program (d) brings power and code
9. 9.🧩 A capacitor in a circuit can … (a) spin a wheel (b) make light (c) measure heat (d) store charge briefly
10. 10.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) series (b) parallel
11. 11.🔘 Which kind of switch stays where you flip it? (a) a push button (b) a toggle switch (c) a tilt switch (d) a reed switch
12. 12.True or false: a rubber eraser is a conductor. (a) True (b) False
13. 13.Which of these is measured in ohms (Ω)? (a) resistance (b) the flow of charge (c) voltage (d) the push of a cell
14. 14.🔌 Is a rubber band a conductor or an insulator? (a) a conductor (b) an insulator
15. 15.⚡ A device works on 3 V and takes 3 A. What is its power (in watts)? =
16. 16.🔌 Is a paper strip a conductor or an insulator? (a) a conductor (b) an insulator
17. 17.⚠️ Someone is getting a shock and is still touching a wire. What should you do? (a) pull them by the hand (b) wait and watch (c) shout for an adult (d) pour water on them
18. 18.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a servo motor (c) a pump (d) a display
19. 19.Which drawing is the symbol for a battery? (a) a dot where wires meet (b) two equal parallel lines (c) many long-short pairs (d) a small empty box
20. 20.Which of these saves electricity? (a) leave the TV on standby (b) run fans in empty rooms (c) leave fridge door open (d) switch off empty rooms
21. 21.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 300 ms }
    How many times does the LED blink in 9 seconds?
22. 22.🔘 Which kind of switch works only while pressed? (a) a push button (b) a tilt switch (c) a slide switch (d) a reed switch
23. 23.🔍 Which is the odd one out? (a) an alert on the phone (b) a motion sensor signal (c) a temperature reading (d) a button press
24. 24.🔺 A current of 10 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
25. 25.Which of these is not safe? (a) dry your hands first (b) use small battery cells (c) stop if a part gets hot (d) poke things in a socket
26. 26.True or false: a circle with a cross is the symbol for a bulb. (a) True (b) False
27. 27.🔺 A current of 2.5 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
28. 28.📏 Which unit measures voltage? (a) watt (W) (b) volt (V) (c) ampere (A) (d) ohm (Ω)
29. 29.⏱️ loop forever { LED ON; wait 1000 ms; LED OFF; wait 300 ms }
    How many milliseconds does one blink (ON + OFF) take?
30. 30.🔺 A current of 0.1 A flows when 0.3 V is joined across a resistor. What is its resistance (in ohms)?
31. 31.⏱️ How many milliseconds is a wait of 0.4 seconds?
32. 32.🔺 In the V-I-R triangle, how do we find R? (a) R = I ÷ V (b) R = V × I (c) R = V + I (d) R = V ÷ I
33. 33.What does a thermistor do? (a) senses how hot it is (b) turns a fan or wheels (c) blows if current is high (d) limits the current
34. 34.🔍 Which is the odd one out? (a) a copper wire (b) a plastic ruler (c) a cotton thread (d) a rubber eraser
35. 35.🔌 Is a buzzer an input or an output for a microcontroller? (a) output (b) input
36. 36.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 3 is taken out of its holder. How many bulbs glow?
37. 37.⏱️ loop forever { LED ON; wait 400 ms; LED OFF; wait 450 ms }
    How many milliseconds does one blink (ON + OFF) take?
38. 38.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a paper strip across the gap. Does the bulb glow? (a) Yes (b) No
39. 39.True or false: to dry your hands first is not safe. (a) False (b) True
40. 40.🔍 Which is the odd one out? (a) a cotton thread (b) a paper strip (c) a rubber band (d) a steel spoon

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