Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 599 · 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.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 10 minutes?
2. 2.True or false: “one out, the rest glow” is true of a parallel circuit. (a) False (b) True
3. 3.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 99000 Ω resistor? (a) white-white-orange (b) white-black-orange (c) white-white-yellow (d) white-white-red
4. 4.Which of these is a conductor? (a) a steel coin (b) a woollen thread (c) a plastic ruler (d) a wooden stick
5. 5.🔋 5 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
6. 6.🔋 3 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
7. 7.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
8. 8.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) an open circuit (b) a safe circuit (c) a short circuit (d) a parallel circuit
9. 9.🔺 A current of 2 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
10. 10.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = V + I (d) P = I ÷ V
11. 11.📶 Digital or analog: a tilt switch: on or off? (a) analog (b) digital
12. 12.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) the else part (c) both parts (d) the if part
13. 13.🔋 How many volts does one ordinary torch cell give? (a) 230 V (b) 15 V (c) 0.5 V (d) 1.5 V
14. 14.Which of these is not an IoT device? (a) a Wi-Fi weather station (b) an app-controlled bulb (c) a Wi-Fi doorbell camera (d) a wind-up clock
15. 15.🔍 Which is the odd one out? (a) aluminium foil (b) a brass key (c) a plastic ruler (d) a safety pin
16. 16.🔁 count = 4
    while (count < 16) { count = count + 2 }
    How many times does the loop run?
17. 17.What does a slide switch do? (a) springs back when let go (b) flips up or down (c) slides side to side (d) stays where you flip it
18. 18.True or false: a wooden stick is an insulator. (a) False (b) True
19. 19.True or false: to use mains for a project is safe. (a) False (b) True
20. 20.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the shorter line (d) the longer line
21. 21.Which of these is not safe? (a) stay away from pylons (b) stop if a part gets hot (c) use small battery cells (d) use mains for a project
22. 22.🧮 A 1.4 V battery is joined to 5 Ω and 2 Ω resistors in series. What current flows (in amperes)? =
23. 23.⚡ What does an electric toy car mainly change electricity into? (a) heat (b) light (c) sound (d) movement
24. 24.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) voltmeter (b) resistor (c) diode (d) capacitor
25. 25.🔍 A distance sensor sends a sound pulse and hears the echo 4 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
26. 26.⚡ What do we call a flow of electric charge through a wire? (a) a magnet (b) friction (c) sound (d) electric current
27. 27.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
28. 28.🔋 A 9 V battery and four 1.5 V cells are joined in series, all facing the same way. What is the total voltage (in volts)? =
29. 29.🔍 Which is the odd one out? (a) a mixer grinder (b) an electric drill (c) a buzzer (d) an exhaust fan
30. 30.True or false: an LDR senses how bright it is. (a) True (b) False
31. 31.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
32. 32.True or false: “a single current path” is true of a series circuit. (a) True (b) False
33. 33.🌈 In the resistor colour code, which number does red stand for?
34. 34.🔘 What does a switch do in a circuit? (a) stores current (b) makes electricity (c) opens or closes the loop (d) changes the voltage
35. 35.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 90 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
36. 36.🔍 Which is the odd one out? (a) count button presses (b) the fan starts (c) compare with a limit (d) check if temp > 30
37. 37.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
38. 38.🔍 Which is the odd one out? (a) share only needed data (b) set up with a parent (c) log out of shared phones (d) share camera links
39. 39.💡 In a series circuit, how many paths does the current have? (a) two (b) none (c) one for each bulb (d) one
40. 40.🔁 x = 2
    repeat 5 times { x = x × 2 }
    What is x at the end?

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