Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 434 · 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.🔢 To plan an electronics project, which is the LAST step? (a) build it with an adult (b) test it and fix it (c) pick a problem to solve (d) list inputs and outputs
2. 2.🔺 A 30 V supply is joined across a 10 Ω resistor. What current flows (in amperes)? =
3. 3.🔁 total = 0
   for i = 1 to 5 { total = total + i }
   What is total at the end?
4. 4.🔺 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
5. 5.💡 A red LED uses 2 V and should get 10 mA. It runs from a 9 V supply. What resistor (in ohms) is needed in series?
6. 6.🧮 A 33 Ω resistor is joined in series with two equal 40 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
7. 7.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) bulb (b) capacitor (c) switch (d) LED
8. 8.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
9. 9.🧮 Two resistors in parallel give a total that is … (a) always zero (b) their sum (c) more than either one (d) less than either one
10. 10.⏱️ loop forever { LED ON; wait 850 ms; LED OFF; wait 100 ms }
    How many milliseconds does one blink (ON + OFF) take?
11. 11.🔁 count = 2
    repeat 7 times { count = count + 2 }
    What is count at the end?
12. 12.🔺 A current of 10 mA flows when 3.3 V is joined across a resistor. What is its resistance (in ohms)?
13. 13.🤖 if (temperature > 32) { fan ON } else { fan OFF }
    The temperature sensor reads 32 °C. What happens? (a) fan ON (b) fan OFF
14. 14.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) False (b) True
15. 15.🔢 To plan an electronics project, which comes first: “draw the circuit diagram” or “list inputs and outputs”? (a) draw the circuit diagram (b) list inputs and outputs
16. 16.Which of these means the circuit is closed? (a) the loop is complete (b) a wire is cut (c) the switch is OFF (d) the bulb is unscrewed
17. 17.⚡ What does an electric drill mainly change electricity into? (a) movement (b) sound (c) light (d) heat
18. 18.🌈 A gold fourth band on a resistor means the value may be off by … (a) 50 % (b) 25 % (c) 5 % (d) 0 %
19. 19.💡 A battery lights 2 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
20. 20.True or false: to touch a switch when wet is safe. (a) False (b) True
21. 21.🔍 Which is the odd one out? (a) a temperature sensor (b) an LED (c) a water pump (d) a motor
22. 22.True or false: “many paths for current” is true of a series circuit. (a) False (b) True
23. 23.🔺 In the V-I-R triangle, how do we find R? (a) R = V + I (b) R = I ÷ V (c) R = V × I (d) R = V ÷ I
24. 24.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
25. 25.🔁 total = 0
    for i = 1 to 9 { total = total + i }
    What is total at the end?
26. 26.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
27. 27.⚠️ Is it safe to climb an electric pole? (a) not safe (b) safe
28. 28.💡 Why is house wiring done in parallel? (a) to save copper only (b) each gets full voltage (c) so all go off together (d) to make bulbs dim
29. 29.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) it does not matter (c) both of them (d) only one
30. 30.🔍 Which is the odd one out? (a) a temperature sensor (b) an LED (c) a motion sensor (d) a push button
31. 31.True or false: the ammeter measures voltage. (a) False (b) True
32. 32.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
33. 33.📶 On a 5 V board, a pin set HIGH gives about … (a) 230 V (b) 50 V (c) 0 V (d) 5 V
34. 34.True or false: one tall, one short bar is the symbol for a junction. (a) True (b) False
35. 35.True or false: “the room temperature” is a digital signal. (a) False (b) True
36. 36.🔺 A current of 25 mA flows when 7.5 V is joined across a resistor. What is its resistance (in ohms)?
37. 37.🔌 Is a temperature sensor an input or an output for a microcontroller? (a) input (b) output
38. 38.True or false: “a break stops every bulb” is true of a parallel circuit. (a) False (b) True
39. 39.True or false: an electric iron mainly gives out heat. (a) True (b) False
40. 40.🔺 A current of 50 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =

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