Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 216 · 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.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
2. 2.Which of these gives us electricity? (a) a water pump (b) a mobile phone (c) a battery (d) a computer
3. 3.Which of these means the circuit is open? (a) the switch is ON (b) the loop is complete (c) the switch is OFF (d) all wires are joined
4. 4.True or false: on a cell, “usually the black wire” means the + (positive) end. (a) True (b) False
5. 5.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is ON and B is OFF. Does the bulb glow? (a) No (b) Yes
6. 6.🔦 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) No (b) Yes
7. 7.🔐 Why install updates on IoT devices? (a) they change the colour (b) they fix security holes (c) they delete the Wi-Fi (d) they make it heavier
8. 8.⏱️ How many milliseconds is a wait of 4.8 seconds?
9. 9.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) stays the same (c) gets smaller (d) gets bigger
10. 10.🔍 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
11. 11.💡 2 identical bulbs are joined in series with a 2 V battery (ideal wires). How many volts does each bulb get? =
12. 12.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) the longer line (c) neither line (d) both lines
13. 13.True or false: the ammeter is joined across a part. (a) True (b) False
14. 14.⚠️ Why must we never touch switches with wet hands? (a) water makes it cold (b) it spoils the paint (c) it is just untidy (d) water carries current
15. 15.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 240 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
16. 16.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 8 HIGH
    set pin 7 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
17. 17.⏱️ repeat 10 times { buzzer ON; wait 1000 ms; buzzer OFF; wait 1000 ms }
    How many milliseconds does this take in all?
18. 18.🔘 Two switches are in series. When does the bulb glow? (a) when both are OFF (b) when either is ON (c) never (d) when both are ON
19. 19.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a push button (c) a reed switch (d) a slide switch
20. 20.🔘 Which kind of switch closes when tipped over? (a) a slide switch (b) a reed switch (c) a toggle switch (d) a tilt switch
21. 21.⏱️ How many milliseconds is a wait of 0.3 seconds?
22. 22.⚠️ Is it safe to fly a kite near wires? (a) safe (b) not safe
23. 23.🔢 To get a sensor reading onto a phone, which comes first: “the cloud stores it” or “the app shows it”? (a) the app shows it (b) the cloud stores it
24. 24.🤖 “if (A AND B)” is true when … (a) only B is true (b) both are false (c) only A is true (d) both A and B are true
25. 25.True or false: a glass marble is an insulator. (a) False (b) True
26. 26.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an output (d) an input
27. 27.🔍 Which is the odd one out? (a) aluminium foil (b) a steel coin (c) a cotton thread (d) a safety pin
28. 28.🧮 Adding another resistor in series makes the total resistance … (a) bigger (b) stay the same (c) zero (d) smaller
29. 29.True or false: “check if temp > 30” is the input. (a) True (b) False
30. 30.⏱️ How many milliseconds is a wait of 1.1 seconds?
31. 31.⚡ Power tells us … (a) the length of a wire (b) the colour of light (c) the size of a cell (d) energy used each second
32. 32.True or false: on an LED, the leg by the flat edge is the cathode (−). (a) True (b) False
33. 33.🔍 Which is the odd one out? (a) a ceiling fan (b) an electric drill (c) an electric toy car (d) an LED lamp
34. 34.🧩 Which component blows if current is high? (a) capacitor (b) fuse (c) thermistor (d) LED
35. 35.🔢 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) it is sent by Wi-Fi
36. 36.🔘 A bulb and a cell are joined through 3 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
37. 37.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 50 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
38. 38.🗺️ In an input → process → output plan, is “a buzzer beeps” the input, the process or the output? (a) input (b) process (c) output
39. 39.🔁 count = 4
    repeat 4 times { count = count + 6 }
    What is count at the end?
40. 40.🔘 A bulb and a cell are joined through 4 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?

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