Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 894 · 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.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) capacitor (b) battery (c) junction (d) wire
2. 2.🔢 To get a sensor reading onto a phone, which is the FIRST step? (a) the app shows it (b) the cloud stores it (c) the sensor measures (d) the board reads it
3. 3.True or false: a microcontroller has a built-in keyboard. (a) False (b) True
4. 4.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) becomes zero (c) gets smaller (d) gets bigger
5. 5.📶 On a 5 V board, a pin set HIGH gives about … (a) 0 V (b) 5 V (c) 50 V (d) 230 V
6. 6.💡 5 identical bulbs are joined in series with a 7.5 V battery (ideal wires). How many volts does each bulb get? =
7. 7.⚠️ Is it safe to touch a switch when wet? (a) not safe (b) safe
8. 8.🗺️ In an input → process → output plan, is “a button press” the input, the process or the output? (a) input (b) output (c) process
9. 9.🔌 Why are electric wires covered in plastic? (a) to make them heavy (b) plastic is a conductor (c) plastic is an insulator (d) plastic makes current
10. 10.🔺 A current of 50 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
11. 11.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 170 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
12. 12.⏱️ repeat 9 times { buzzer ON; wait 400 ms; buzzer OFF; wait 300 ms }
    How many milliseconds does this take in all?
13. 13.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
14. 14.True or false: a toy robot has no microcontroller inside. (a) True (b) False
15. 15.💡 2 identical bulbs are in parallel and each one takes 0.5 A. What total current (in amperes) comes from the battery? =
16. 16.🤖 Microcontroller or laptop: which one runs many apps at once? (a) laptop (b) microcontroller
17. 17.Which of these means the circuit is open? (a) the loop is complete (b) all wires are joined (c) a wire has come loose (d) the switch is ON
18. 18.🌐 A soil sensor sends a reading to an app every 20 minutes. How many readings arrive in 3 hours?
19. 19.🌈 A resistor has the colour bands violet, yellow, brown. What is its value (in ohms)?
20. 20.🌐 A weather station sends one reading every 15 seconds. How many readings does it send in 6 minutes?
21. 21.🔺 A current of 0.25 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
22. 22.True or false: a microwave oven has no microcontroller inside. (a) True (b) False
23. 23.Which of these mainly gives out light? (a) a ceiling fan (b) a street light (c) an exhaust fan (d) a siren
24. 24.⚠️ Is it safe to fly kites in open fields? (a) not safe (b) safe
25. 25.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a program (d) a battery
26. 26.True or false: a plain wall switch has no microcontroller inside. (a) False (b) True
27. 27.🌐 In an IoT system, which part measures the real world? (a) phone app (b) sensor (c) cloud server (d) actuator
28. 28.📏 How many ohms (Ω) is 8.7 kΩ?
29. 29.🔌 Is a keypad an input or an output for a microcontroller? (a) input (b) output
30. 30.🔘 A bulb and a cell are joined through 4 switches on 4 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
31. 31.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 20 °C. What is shown? (a) Warm (b) Hot (c) Cool
32. 32.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) bigger (d) smaller
33. 33.True or false: to cover unused cameras is a risky habit. (a) False (b) True
34. 34.⏱️ How many milliseconds is a wait of 1.5 seconds?
35. 35.⚡ What do we call a flow of electric charge through a wire? (a) electric current (b) sound (c) a magnet (d) friction
36. 36.True or false: “a single current path” is true of a series circuit. (a) False (b) True
37. 37.Which of these is measured in volts (V)? (a) current (b) resistance (c) voltage (d) how much a part resists
38. 38.⚠️ Which power source should children use for electronics projects? (a) a wall socket (b) a mains extension board (c) a small battery pack (d) an inverter socket
39. 39.🔦 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
40. 40.💡 What happens if an LED is put in backwards? (a) it lights brighter (b) it does not light (c) it changes colour (d) it makes a sound

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