Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 195 · 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.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) switch the pump on/off (b) wait a few seconds (c) compare with the limit
2. 2.💡 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
3. 3.🔢 To plan an electronics project, what comes right after “list inputs and outputs”? (a) pick a problem to solve (b) build it with an adult (c) test it and fix it (d) draw the circuit diagram
4. 4.True or false: to change default passwords is a risky habit. (a) False (b) True
5. 5.⚡ Power tells us … (a) the length of a wire (b) the size of a cell (c) energy used each second (d) the colour of light
6. 6.True or false: “own switch for each bulb” is true of a series circuit. (a) True (b) False
7. 7.⚡ A 1.5 W device works on 1.5 V. What current does it take (in amperes)? =
8. 8.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is ON and C is ON. Does the bulb glow? (a) Yes (b) No
9. 9.📏 How many ohms (Ω) is 1.6 kΩ?
10. 10.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) motor (b) capacitor (c) bulb (d) wire
11. 11.Which of these is the process? (a) the fan starts (b) compare with a limit (c) a light level reading (d) a soil moisture reading
12. 12.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) gets bigger (c) gets smaller (d) stays the same
13. 13.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
14. 14.⏱️ loop forever { LED ON; wait 950 ms; LED OFF; wait 750 ms }
    How many milliseconds does one blink (ON + OFF) take?
15. 15.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
16. 16.🔁 total = 0
    for i = 1 to 6 { total = total + i }
    What is total at the end?
17. 17.Which of these means the circuit is closed? (a) a wire has come loose (b) a cell is taken out (c) all wires are joined (d) the bulb is unscrewed
18. 18.💡 A red LED (it uses 2 V) is joined with a 200 Ω resistor to a 6 V supply. What current flows (in mA)?
19. 19.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) output (b) process (c) input
20. 20.True or false: to ignore update messages is a risky habit. (a) True (b) False
21. 21.💡 4 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. Bulbs 2 and 3 are taken out of their holders. How many bulbs glow?
22. 22.🔁 What does “count = count + 1” do? (a) prints 1 (b) sets count to 1 (c) takes 1 away (d) adds 1 to count
23. 23.True or false: one tall, one short bar is the symbol for a switch. (a) False (b) True
24. 24.🔍 Which is the odd one out? (a) a plastic ruler (b) a copper wire (c) a paper strip (d) a wooden stick
25. 25.🌈 A resistor has the colour bands grey, yellow, red. What is its value in kilo-ohms (kΩ)? =
26. 26.🔐 Is it a good or a risky habit to set up with a parent? (a) good habit (b) risky habit
27. 27.⚡ A device works on 3 V and takes 1 A. What is its power (in watts)? =
28. 28.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
29. 29.🏠 Which is a smart-home example? (a) a hand fan (b) a printed map (c) a candle in a jar (d) lights on from an app
30. 30.⏱️ loop forever { LED ON; wait 700 ms; LED OFF; wait 250 ms }
    How many milliseconds does one blink (ON + OFF) take?
31. 31.Which of these uses electricity? (a) a solar panel (b) a generator (c) a power station (d) a computer
32. 32.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 110 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
33. 33.🔺 A current of 20 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
34. 34.💡 What happens if an LED is put in backwards? (a) it lights brighter (b) it makes a sound (c) it does not light (d) it changes colour
35. 35.🔍 Which is the odd one out? (a) share the Wi-Fi key (b) turn off unused gadgets (c) accept every permission (d) share camera links
36. 36.📏 How many kilo-ohms (kΩ) is 2600 Ω? =
37. 37.True or false: “how loud a sound is” is a digital signal. (a) True (b) False
38. 38.🧩 A capacitor in a circuit can … (a) store charge briefly (b) make light (c) measure heat (d) spin a wheel
39. 39.🤖 “if (A AND B)” is true when … (a) only A is true (b) both are false (c) both A and B are true (d) only B is true
40. 40.⚡ What does an LED lamp mainly change electricity into? (a) light (b) movement (c) sound (d) heat

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