Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 707 · 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.True or false: a tilt switch closes when tipped over. (a) False (b) True
2. 2.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 5 V supply. What current flows (in mA)?
3. 3.💡 2 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
4. 4.💡 What happens if an LED is put in backwards? (a) it changes colour (b) it does not light (c) it lights brighter (d) it makes a sound
5. 5.🌐 Is a paper calendar an IoT device? (a) an IoT device (b) not an IoT device
6. 6.Which drawing is the symbol for a battery? (a) two equal parallel lines (b) two or more cell symbols (c) a circle with V inside (d) a plain rectangle
7. 7.True or false: a slide switch slides side to side. (a) False (b) True
8. 8.Which of these is not safe? (a) stop if a part gets hot (b) keep drinks far away (c) climb an electric pole (d) use small battery cells
9. 9.What does a slide switch do? (a) slides side to side (b) closes when tipped over (c) springs back when let go (d) flips up or down
10. 10.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 21) { show “Warm” } else { show “Cool” }
    The temperature is 34 °C. What is shown? (a) Hot (b) Cool (c) Warm
11. 11.🤖 if (temperature > 25) { fan ON } else { fan OFF }
    The temperature sensor reads 18 °C. What happens? (a) fan OFF (b) fan ON
12. 12.Which of these gives us electricity? (a) a bicycle dynamo (b) an air conditioner (c) a computer (d) a television
13. 13.📏 How many milliamperes (mA) is 0.41 A?
14. 14.🔢 To get a sensor reading onto a phone, which is the LAST step? (a) the board reads it (b) the cloud stores it (c) the app shows it (d) the sensor measures
15. 15.Which of these means the circuit is closed? (a) a cell is taken out (b) a wire is cut (c) a wire has come loose (d) the switch is ON
16. 16.🔺 A 16.5 V supply is joined across a 330 Ω resistor. What current flows (in milliamperes, mA)?
17. 17.🔁 count = 0
    repeat 4 times { count = count + 9 }
    What is count at the end?
18. 18.🔁 total = 0
    for i = 1 to 11 { total = total + i }
    What is total at the end?
19. 19.⚡ A 36 W device works on 24 V. What current does it take (in amperes)? =
20. 20.🔢 To get a sensor reading onto a phone, which comes first: “the sensor measures” or “the board reads it”? (a) the sensor measures (b) the board reads it
21. 21.True or false: “a break stops every bulb” is true of a series circuit. (a) False (b) True
22. 22.🔋 How many 1.2 V cells must be joined in series to give 3.6 V?
23. 23.🧩 Which component stores a little charge? (a) LDR (b) capacitor (c) buzzer (d) motor
24. 24.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
25. 25.📏 How many kilo-ohms (kΩ) is 1300 Ω? =
26. 26.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the power LED (b) the reset button (c) the main chip (d) the pins
27. 27.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. How many bulbs glow?
28. 28.🔐 Is it a good or a risky habit to ignore update messages? (a) risky habit (b) good habit
29. 29.🌐 Is a Wi-Fi smart plug an IoT device? (a) not an IoT device (b) an IoT device
30. 30.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 400 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
31. 31.🔢 To get a sensor reading onto a phone, which is the FIRST step? (a) the board reads it (b) it is sent by Wi-Fi (c) the sensor measures (d) the cloud stores it
32. 32.🔺 A current of 10 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
33. 33.True or false: the ammeter is joined in series. (a) False (b) True
34. 34.🔘 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) Yes (b) No
35. 35.True or false: on an LED, the round-side leg is the cathode (−). (a) False (b) True
36. 36.🔐 Who should decide which smart devices go in a child’s room? (a) the app’s adverts (b) an online stranger (c) nobody at all (d) a parent or guardian
37. 37.🔋 How many volts does one ordinary torch cell give? (a) 0.5 V (b) 230 V (c) 1.5 V (d) 15 V
38. 38.🔋 Identical cells side by side (in parallel) give … (a) double the voltage (b) no voltage (c) half the voltage (d) the same voltage
39. 39.🌐 Is a pencil sharpener an IoT device? (a) an IoT device (b) not an IoT device
40. 40.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V ÷ I (c) P = V × I (d) P = V + I

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