Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 142 · 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.🔌 Is a motor an input or an output for a microcontroller? (a) output (b) input
2. 2.🔍 Which is the odd one out? (a) use LED lamps (b) use daylight to read (c) close the fridge quickly (d) use old filament bulbs
3. 3.🧩 Which component boosts a small signal? (a) transistor (b) capacitor (c) fuse (d) LDR
4. 4.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a rubber eraser across the gap. Does the bulb glow? (a) Yes (b) No
5. 5.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 90 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
6. 6.🔁 count = 6
   repeat 5 times { count = count + 4 }
   What is count at the end?
7. 7.True or false: “the room temperature” is a digital signal. (a) True (b) False
8. 8.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) True (b) False
9. 9.🤖 if (temperature > 32) { fan ON } else { fan OFF }
   The temperature sensor reads 32 °C. What happens? (a) fan ON (b) fan OFF
10. 10.⏱️ loop forever { LED ON; wait 750 ms; LED OFF; wait 400 ms }
    How many milliseconds does one blink (ON + OFF) take?
11. 11.🌈 A gold fourth band on a resistor means the value may be off by … (a) 5 % (b) 50 % (c) 25 % (d) 0 %
12. 12.🔋 How many 1.2 V cells must be joined in series to give 6 V?
13. 13.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
14. 14.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) gets bigger (c) stays the same (d) becomes zero
15. 15.📏 Which unit measures the push of a cell? (a) ampere (A) (b) ohm (Ω) (c) volt (V) (d) watt (W)
16. 16.True or false: “a single current path” is true of a series circuit. (a) False (b) True
17. 17.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) not joined (c) in parallel (d) by Wi-Fi
18. 18.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) No (b) Yes
19. 19.True or false: a thermistor glows using little power. (a) False (b) True
20. 20.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 1 glow? (a) No (b) Yes
21. 21.⏱️ A program says “wait 750 ms”. How many seconds is that? =
22. 22.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 kilowatt-hour (kWh) (c) 1 volt (d) 1 watt
23. 23.📏 Which unit measures voltage? (a) ohm (Ω) (b) volt (V) (c) ampere (A) (d) watt (W)
24. 24.Which of these is safe? (a) fly a kite near wires (b) climb an electric pole (c) stop if a part gets hot (d) touch a switch when wet
25. 25.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 25 cm. What happens? (a) buzzer is silent (b) buzzer beeps
26. 26.True or false: a toggle switch slides side to side. (a) False (b) True
27. 27.🔁 count = 9
    repeat 8 times { count = count + 9 }
    What is count at the end?
28. 28.🔍 Which is the odd one out? (a) throw cells in a fire (b) open a phone charger (c) stop if a part gets hot (d) fly a kite near wires
29. 29.🧮 Two equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
30. 30.⚠️ Is it safe to build with an adult near? (a) safe (b) not safe
31. 31.🔍 A distance sensor sends a sound pulse and hears the echo 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
32. 32.🤖 if (temperature > 30) { fan ON } else { fan OFF }
    The temperature sensor reads 25 °C. What happens? (a) fan OFF (b) fan ON
33. 33.🔌 Is a water pump an input or an output for a microcontroller? (a) input (b) output
34. 34.What does the sensor do? (a) carries the data (b) acts on a command (c) measures the real world (d) shows data to you
35. 35.🤖 Does a smart watch usually have a microcontroller inside? (a) No (b) Yes
36. 36.Which of these is not safe? (a) stop if a part gets hot (b) build with an adult near (c) take cells out after use (d) use a cable with cuts
37. 37.🔺 A 16 V supply is joined across a 400 Ω resistor. What current flows (in milliamperes, mA)?
38. 38.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a steel spoon across the gap. Does the bulb glow? (a) No (b) Yes
39. 39.True or false: “a buzzer beeps” is the output. (a) False (b) True
40. 40.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) False (b) True

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