Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 990 · 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 single current path” is true of a parallel circuit. (a) True (b) False
2. 2.📏 Voltmeter or ammeter: which one measures current? (a) voltmeter (b) ammeter
3. 3.🔢 To plan an electronics project, which comes first: “pick a problem to solve” or “list inputs and outputs”? (a) pick a problem to solve (b) list inputs and outputs
4. 4.🧮 Resistors of 47 Ω, 33 Ω, 47 Ω and 22 Ω are joined in series. What is the total resistance (in ohms)?
5. 5.⚡ A device works on 9 V and takes 0.5 A. What is its power (in watts)? =
6. 6.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
7. 7.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) put it in the bathroom (b) mute it when not in use (c) let strangers use it (d) tell it your passwords
8. 8.🔘 Which kind of switch closes near a magnet? (a) a slide switch (b) a toggle switch (c) a tilt switch (d) a reed switch
9. 9.🧭 Which part of a microcontroller board runs the program? (a) the main chip (b) the voltage regulator (c) the power LED (d) the USB port
10. 10.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) the if part (c) neither part (d) the else part
11. 11.🔋 Does a computer give electricity or use electricity? (a) uses electricity (b) gives electricity
12. 12.True or false: two or more cell symbols is the symbol for a battery. (a) False (b) True
13. 13.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in series (c) not joined (d) in parallel
14. 14.True or false: “a button: pressed or not” is a digital signal. (a) True (b) False
15. 15.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) symbols are heavier (c) quick and clear for all (d) to hide the circuit
16. 16.🔐 Is it a good or a risky habit to share camera links? (a) good habit (b) risky habit
17. 17.🌐 Is a Wi-Fi weather station an IoT device? (a) not an IoT device (b) an IoT device
18. 18.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
19. 19.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a rubber eraser. Does the bulb glow? (a) No (b) Yes
20. 20.🔍 Which is the odd one out? (a) a cotton thread (b) aluminium foil (c) a steel spoon (d) a copper wire
21. 21.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) never (c) when both are OFF (d) when both are ON
22. 22.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 8 LOW
    set pin 8 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
23. 23.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 100 (d) 1000
24. 24.True or false: “bulbs share the voltage” is true of a series circuit. (a) False (b) True
25. 25.True or false: to stop if a part gets hot is safe. (a) False (b) True
26. 26.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) becomes zero (c) gets bigger (d) gets smaller
27. 27.Which of these is an output? (a) a turning knob (b) a motion sensor (c) a sound sensor (d) a small display
28. 28.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = R ÷ I (c) V = I ÷ R (d) V = I × R
29. 29.🔺 A current of 0.5 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
30. 30.Which of these means the circuit is open? (a) the loop is complete (b) the bulb is unscrewed (c) all wires are joined (d) the switch is ON
31. 31.🔺 A current of 50 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
32. 32.True or false: to keep an incubator warm, use a motion sensor. (a) False (b) True
33. 33.🔁 count = 1
    while (count < 31) { count = count + 5 }
    How many times does the loop run?
34. 34.⏱️ How many milliseconds is a wait of 0.4 seconds?
35. 35.Which of these is true of a parallel circuit? (a) used in house wiring (b) bulbs share the voltage (c) a break stops every bulb (d) a single current path
36. 36.🌈 A resistor has the colour bands grey, brown, black. What is its value (in ohms)?
37. 37.🧮 A 3.25 V battery is joined to 10 Ω and 3 Ω resistors in series. What current flows (in amperes)? =
38. 38.🔍 Which is the odd one out? (a) a temperature reading (b) an alert on the phone (c) a light level reading (d) a button press
39. 39.What does the sensor do? (a) measures the real world (b) reads values, decides (c) shows data to you (d) acts on a command
40. 40.📏 How many milliamperes (mA) is 0.13 A?

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