Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 791 · 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.🔺 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
2. 2.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) cell (b) LED (c) capacitor (d) resistor
3. 3.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a brass key across the gap. Does the bulb glow? (a) Yes (b) No
4. 4.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) both lines (c) the longer line (d) the shorter line
5. 5.🔐 Who should decide which smart devices go in a child’s room? (a) an online stranger (b) the app’s adverts (c) nobody at all (d) a parent or guardian
6. 6.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) bigger (d) smaller
7. 7.✏️ Why do engineers draw circuits with symbols? (a) to hide the circuit (b) to make it colourful (c) quick and clear for all (d) symbols are heavier
8. 8.True or false: a circle with a cross is the symbol for a switch. (a) True (b) False
9. 9.🗺️ In an input → process → output plan, is “a temperature reading” the input, the process or the output? (a) process (b) output (c) input
10. 10.🔁 What must there be for a current to flow? (a) a broken path (b) one loose end (c) a plastic gap (d) a complete loop
11. 11.🔋 7 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
12. 12.True or false: a motor stores a little charge. (a) False (b) True
13. 13.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. How many bulbs glow?
14. 14.⚡ What do we call a flow of electric charge through a wire? (a) friction (b) electric current (c) sound (d) a magnet
15. 15.🔋 Does a power station give electricity or use electricity? (a) uses electricity (b) gives electricity
16. 16.True or false: a mixer grinder mainly makes sound. (a) True (b) False
17. 17.🔐 Is it a good or a risky habit to change default passwords? (a) good habit (b) risky habit
18. 18.🧮 Three equal 30 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
19. 19.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
20. 20.🤖 if (distance < 15) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 23 cm. What happens? (a) buzzer is silent (b) buzzer beeps
21. 21.Which job needs a sound sensor? (a) open blinds at sunrise (b) close a window in rain (c) switch on lamps at dusk (d) switch on with a clap
22. 22.💡 Why is house wiring done in parallel? (a) each gets full voltage (b) to save copper only (c) so all go off together (d) to make bulbs dim
23. 23.Which of these is true of a parallel circuit? (a) own switch for each bulb (b) a break stops every bulb (c) bulbs share the voltage (d) one bulb out, all go out
24. 24.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) a candle (c) an oil lamp (d) an LED lamp
25. 25.💡 3 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
26. 26.🧩 Which component smooths a wobbly supply? (a) fuse (b) buzzer (c) capacitor (d) thermistor
27. 27.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
28. 28.True or false: to use daylight to read saves electricity. (a) False (b) True
29. 29.🔌 Is a servo motor an input or an output for a microcontroller? (a) output (b) input
30. 30.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = V × R (c) I = V ÷ R (d) I = R ÷ V
31. 31.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) little stars (c) wavy lines (d) dotted circles
32. 32.What does a toggle switch do? (a) works only while pressed (b) slides side to side (c) stays where you flip it (d) springs back when let go
33. 33.🧩 A capacitor in a circuit can … (a) measure heat (b) store charge briefly (c) make light (d) spin a wheel
34. 34.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) False (b) True
35. 35.⚠️ Who should be with you when you build a circuit? (a) a younger child (b) a stranger online (c) a trusted adult (d) nobody
36. 36.⏱️ How many milliseconds is a wait of 2.7 seconds?
37. 37.📏 Which unit measures resistance? (a) volt (V) (b) watt (W) (c) ampere (A) (d) ohm (Ω)
38. 38.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
39. 39.Which of these is the process? (a) a temperature reading (b) a light level reading (c) an LED lights up (d) decide if soil is dry
40. 40.🔐 Is it a good or a risky habit to set up with a parent? (a) risky habit (b) good habit

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