Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 685 · 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 smart-camera app asks for your school name and home address. What should you do? (a) type it all in (b) share it with friends (c) post it online (d) ask a parent first
2. 2.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 8 HIGH
   set pin 8 LOW
   set pin 8 LOW
   set pin 8 HIGH
   set pin 8 HIGH
   Is the LED ON or OFF at the end? (a) ON (b) OFF
3. 3.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a wooden stick. Does the bulb glow? (a) No (b) Yes
4. 4.🔺 A current of 50 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
5. 5.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) False (b) True
6. 6.📶 A pin set LOW gives about … (a) 0 V (b) 9 V (c) 5 V (d) 1.5 V
7. 7.✏️ In a circuit diagram, which part is drawn as a circle with V inside? (a) ammeter (b) cell (c) bulb (d) voltmeter
8. 8.📏 Voltmeter or ammeter: which one measures voltage? (a) voltmeter (b) ammeter
9. 9.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a plastic ruler. Does the bulb glow? (a) Yes (b) No
10. 10.🤖 Does a wind-up toy usually have a microcontroller inside? (a) No (b) Yes
11. 11.🔍 Which sensor would you use to switch on with a clap? (a) a soil moisture sensor (b) a sound sensor (c) a distance sensor (d) a rain sensor
12. 12.⚡ A 1.2 W device works on 12 V. What current does it take (in amperes)? =
13. 13.⚡ A fan changes electrical energy mainly into which kind of energy? (a) sound energy (b) movement energy (c) light energy (d) chemical energy
14. 14.🔘 Which kind of switch works only while pressed? (a) a tilt switch (b) a push button (c) a reed switch (d) a slide switch
15. 15.True or false: to iron one shirt at a time wastes electricity. (a) False (b) True
16. 16.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
17. 17.🔐 Is it a good or a risky habit to post your live location? (a) good habit (b) risky habit
18. 18.🌈 Which band is read first on a resistor? (a) the gold band (b) any band (c) the one nearest an end (d) the widest gap
19. 19.📏 How many milliamperes (mA) is 1.63 A?
20. 20.True or false: to leave the TV on standby saves electricity. (a) True (b) False
21. 21.What does a fuse do? (a) stores a little charge (b) senses how hot it is (c) boosts a small signal (d) blows if current is high
22. 22.🔘 Which kind of switch flips up or down? (a) a toggle switch (b) a slide switch (c) a tilt switch (d) a push button
23. 23.🔺 A current of 2.5 A flows when 37.5 V is joined across a resistor. What is its resistance (in ohms)?
24. 24.🔘 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?
25. 25.🔐 Which is the strongest password for a home smart camera? (a) Tiger#Lamp42!Moon (b) admin (c) 123456 (d) password
26. 26.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave fridge door open (c) use old filament bulbs (d) close the fridge quickly
27. 27.True or false: a graphite rod is an insulator. (a) False (b) True
28. 28.🌈 A resistor has the colour bands yellow, orange, red. What is its value (in ohms)?
29. 29.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
30. 30.⚠️ Is it safe to touch a switch when wet? (a) safe (b) not safe
31. 31.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) the shorter line (c) neither line (d) the longer line
32. 32.True or false: the push of a cell is measured in ohms (Ω). (a) False (b) True
33. 33.🗺️ In an input → process → output plan, is “the pump turns on” the input, the process or the output? (a) input (b) process (c) output
34. 34.⚠️ Is it safe to keep drinks far away? (a) safe (b) not safe
35. 35.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
36. 36.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
37. 37.Which drawing is the symbol for a capacitor? (a) triangle, bar and arrows (b) a circle with V inside (c) two equal parallel lines (d) a circle with a cross
38. 38.Which job needs a motion sensor? (a) measure classroom noise (b) make a parking alarm (c) spot someone walking in (d) keep an incubator warm
39. 39.🌈 In the resistor colour code, which number does violet stand for?
40. 40.🧮 A 100 Ω resistor is joined in series with two equal 20 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?

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