Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 649 · 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.Which drawing is the symbol for a motor? (a) a circle with A inside (b) one tall, one short bar (c) a circle with an X in it (d) a circle with M inside
2. 2.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
3. 3.🔺 A current of 1 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
4. 4.⚠️ Is it safe to use small battery cells? (a) not safe (b) safe
5. 5.Which job is done by the reset button? (a) keeps the voltage steady (b) runs the program (c) brings power and code (d) restarts the program
6. 6.⏱️ How many milliseconds is a wait of 1.3 seconds?
7. 7.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) in parallel (c) by Wi-Fi (d) not joined
8. 8.📏 Voltmeter or ammeter: which one is joined in series? (a) ammeter (b) voltmeter
9. 9.🔍 Which is the odd one out? (a) run fans in empty rooms (b) set the AC to 24 °C (c) leave fridge door open (d) leave the TV on standby
10. 10.🗺️ In an input → process → output plan, is “an alert on the phone” the input, the process or the output? (a) input (b) process (c) output
11. 11.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) neither part (c) the else part (d) the if part
12. 12.⏱️ How many milliseconds are in 1 second? (a) 100 (b) 1000 (c) 60 (d) 10
13. 13.True or false: a capacitor turns a fan or wheels. (a) True (b) False
14. 14.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. How many bulbs glow?
15. 15.Which of these is an input? (a) a motion sensor (b) a motor (c) a speaker (d) a servo motor
16. 16.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an output (c) a power source (d) an input
17. 17.⚡ What does a water heater mainly change electricity into? (a) light (b) sound (c) heat (d) movement
18. 18.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) LED (b) resistor (c) capacitor (d) switch
19. 19.🧩 A capacitor in a circuit can … (a) make light (b) spin a wheel (c) measure heat (d) store charge briefly
20. 20.Which of these is measured in volts (V)? (a) the flow of charge (b) the push of a cell (c) how much a part resists (d) resistance
21. 21.True or false: an LED lamp mainly makes sound. (a) False (b) True
22. 22.🔍 Which is the odd one out? (a) fly kites in open fields (b) use mains for a project (c) keep drinks far away (d) stay away from pylons
23. 23.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
24. 24.True or false: to share only needed data is a risky habit. (a) True (b) False
25. 25.🔋 What should you do with used-up cells? (a) bury them in soil (b) cut them open (c) throw them in a fire (d) give them for recycling
26. 26.True or false: on an LED, the round-side leg is the cathode (−). (a) True (b) False
27. 27.True or false: a plain rectangle is the symbol for a diode. (a) False (b) True
28. 28.🔌 Which part of a screwdriver should an electrician hold? (a) the plastic handle (b) the bare end (c) the steel shaft (d) the metal tip
29. 29.🌐 In an IoT system, which part measures the real world? (a) phone app (b) actuator (c) sensor (d) microcontroller
30. 30.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the battery (b) the output (c) the process (d) the input
31. 31.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) LED (b) cell (c) battery (d) motor
32. 32.🔍 Which is the odd one out? (a) a motor (b) a water pump (c) a servo motor (d) a motion sensor
33. 33.💡 In a series circuit, how many paths does the current have? (a) none (b) one (c) one for each bulb (d) two
34. 34.🔘 What does a switch do in a circuit? (a) stores current (b) changes the voltage (c) makes electricity (d) opens or closes the loop
35. 35.Which of these mainly makes movement? (a) a street light (b) a torch (c) a toaster (d) a table fan
36. 36.💡 Why does an LED need a resistor in series? (a) to make it brighter (b) to store charge (c) to limit the current (d) to change its colour
37. 37.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to an 8 V supply. What current flows (in mA)?
38. 38.🤖 Microcontroller or laptop: which one has no screen of its own? (a) laptop (b) microcontroller
39. 39.⏱️ loop forever { LED ON; wait 950 ms; LED OFF; wait 1050 ms }
    How many times does the LED blink in 20 seconds?
40. 40.🔁 repeat 5 times { repeat 5 times { beep } }
    How many beeps are there?

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