Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 268 · 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.⏱️ repeat 2 times { buzzer ON; wait 300 ms; buzzer OFF; wait 400 ms }
   How many milliseconds does this take in all?
2. 2.What does a slide switch do? (a) slides side to side (b) stays where you flip it (c) closes when tipped over (d) works only while pressed
3. 3.🌐 Is a Wi-Fi weather station an IoT device? (a) an IoT device (b) not an IoT device
4. 4.🔌 Is a motion sensor an input or an output for a microcontroller? (a) output (b) input
5. 5.🔍 Which is the odd one out? (a) install software updates (b) turn off unused gadgets (c) tap unknown app links (d) change default passwords
6. 6.📏 In the water-pipe picture of a circuit, voltage is like … (a) the pipe colour (b) the tap handle (c) the water tank lid (d) the water pressure
7. 7.Which of these saves electricity? (a) use LED lamps (b) run fans in empty rooms (c) leave fridge door open (d) leave the TV on standby
8. 8.🔋 Does a solar panel give electricity or use electricity? (a) gives electricity (b) uses electricity
9. 9.🔋 7 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
10. 10.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
11. 11.True or false: an electric kettle mainly makes sound. (a) False (b) True
12. 12.🔢 To get a sensor reading onto a phone, what comes right after “it is sent by Wi-Fi”? (a) the app shows it (b) the sensor measures (c) the board reads it (d) the cloud stores it
13. 13.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) in series (c) by Wi-Fi (d) in parallel
14. 14.Which drawing is the symbol for a junction? (a) a circle with A inside (b) a dot where wires meet (c) one tall, one short bar (d) two equal parallel lines
15. 15.⏱️ repeat 6 times { buzzer ON; wait 200 ms; buzzer OFF; wait 600 ms }
    How many milliseconds does this take in all?
16. 16.True or false: “a break stops every bulb” is true of a parallel circuit. (a) False (b) True
17. 17.💡 Why is house wiring done in parallel? (a) so all go off together (b) to save copper only (c) each gets full voltage (d) to make bulbs dim
18. 18.⏱️ loop forever { LED ON; wait 750 ms; LED OFF; wait 350 ms }
    How many milliseconds does one blink (ON + OFF) take?
19. 19.🔍 Which is the odd one out? (a) use daylight to read (b) use LED lamps (c) leave the TV on standby (d) unplug idle chargers
20. 20.💡 3 identical bulbs are in parallel and each one takes 0.2 A. What total current (in amperes) comes from the battery? =
21. 21.🧮 A 20 Ω resistor is joined in series with two equal 100 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
22. 22.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
23. 23.True or false: a circle with A inside is the symbol for an ammeter. (a) False (b) True
24. 24.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) none (c) two (d) one
25. 25.🧮 Three equal 75 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
26. 26.What does a fuse do? (a) blows if current is high (b) lets current go one way (c) beeps for an alarm (d) makes things spin
27. 27.True or false: a push button springs back when let go. (a) True (b) False
28. 28.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) neither line (d) both lines
29. 29.True or false: to set a strong password is a risky habit. (a) True (b) False
30. 30.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 1000 (c) 60 (d) 100
31. 31.True or false: “used in house wiring” is true of a series circuit. (a) False (b) True
32. 32.What does the actuator do? (a) shows data to you (b) measures the real world (c) acts on a command (d) stores data online
33. 33.🔍 Which is the odd one out? (a) share the Wi-Fi key (b) share only needed data (c) install software updates (d) change default passwords
34. 34.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 50 % (c) 25 % (d) 5 %
35. 35.🔍 Which is the odd one out? (a) a small display (b) a servo motor (c) an LED (d) a motion sensor
36. 36.True or false: “a button press” is the process. (a) True (b) False
37. 37.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an input (c) a fuse (d) an output
38. 38.🔋 Does a water pump give electricity or use electricity? (a) gives electricity (b) uses electricity
39. 39.🧩 A capacitor in a circuit can … (a) measure heat (b) make light (c) spin a wheel (d) store charge briefly
40. 40.🔺 A current of 20 mA flows through a 400 Ω resistor. What is the voltage across it (in volts)? =

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