Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 804 · 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.⏱️ A program says “wait 9500 ms”. How many seconds is that? =
2. 2.🧩 Which component blows if current is high? (a) motor (b) buzzer (c) resistor (d) fuse
3. 3.True or false: a water heater mainly makes sound. (a) False (b) True
4. 4.🔌 Most metals are good … (a) batteries (b) conductors (c) magnets only (d) insulators
5. 5.🧩 Which component glows using little power? (a) buzzer (b) thermistor (c) LED (d) potentiometer
6. 6.🔺 A current of 0.2 A flows when 0.8 V is joined across a resistor. What is its resistance (in ohms)?
7. 7.🔌 Is a graphite rod a conductor or an insulator? (a) a conductor (b) an insulator
8. 8.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 50 % (c) 25 % (d) 5 %
9. 9.🔁 repeat 2 times { repeat 3 times { beep } }
   How many beeps are there?
10. 10.Which job needs a motor? (a) turn to an exact angle (b) spin a robot’s wheels (c) move water to plants (d) beep an alarm
11. 11.⚠️ Is it safe to use small battery cells? (a) not safe (b) safe
12. 12.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
13. 13.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
14. 14.⚡ What does a toaster mainly change electricity into? (a) sound (b) light (c) heat (d) movement
15. 15.⚡ A home appliance on the 230 V mains takes 4 A. What is its power (in watts)?
16. 16.🔁 repeat 6 times { repeat 6 times { beep } }
    How many beeps are there?
17. 17.Which drawing is the symbol for a cell? (a) a circle with A inside (b) a small empty box (c) a long and a short line (d) a circle with an X in it
18. 18.⚠️ Who should be with you when you build a circuit? (a) nobody (b) a younger child (c) a trusted adult (d) a stranger online
19. 19.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
20. 20.🔍 Which sensor would you use to make a parking alarm? (a) a gas sensor (b) a sound sensor (c) a soil moisture sensor (d) a distance sensor
21. 21.🌈 A resistor has the colour bands orange, brown, brown. What is its value (in ohms)?
22. 22.⚡ Which formula gives electric power? (a) P = V + I (b) P = V ÷ I (c) P = V × I (d) P = I ÷ V
23. 23.True or false: a brass key is a conductor. (a) True (b) False
24. 24.⏱️ How many milliseconds is a wait of 0.2 seconds?
25. 25.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
26. 26.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) closed (b) open
27. 27.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) bigger (c) stay the same (d) zero
28. 28.🤖 Microcontroller or laptop: which one runs many apps at once? (a) laptop (b) microcontroller
29. 29.True or false: to build with an adult near is not safe. (a) True (b) False
30. 30.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the longer line (d) the shorter line
31. 31.💡 A battery lights 4 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
32. 32.⏱️ loop forever { LED ON; wait 1250 ms; LED OFF; wait 750 ms }
    How many times does the LED blink in 16 seconds?
33. 33.True or false: a loudspeaker mainly makes sound. (a) False (b) True
34. 34.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) pauses for half a second (c) blinks 500 times (d) turns the LED off
35. 35.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they get dimmer (c) they keep glowing (d) they all go out
36. 36.🧮 Resistors of 470 Ω and 20 Ω are joined in series. What is the total resistance (in ohms)?
37. 37.💡 A battery lights 2 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
38. 38.🔁 What does a variable do in a program? (a) blinks an LED (b) stores a value (c) joins two wires (d) measures light
39. 39.True or false: to fly a kite near wires is not safe. (a) True (b) False
40. 40.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No

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