Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 386 · 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 60 seconds. How many readings does it send in 1 minute?
2. 2.Which of these is an insulator? (a) a graphite rod (b) a rubber band (c) a steel spoon (d) an iron nail
3. 3.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
4. 4.Which of these is an IoT device? (a) a wind-up clock (b) a paper calendar (c) a pencil sharpener (d) a smart energy meter
5. 5.🔍 Which is the odd one out? (a) a wind-up clock (b) a Wi-Fi smart plug (c) an app-controlled bulb (d) a fitness band with app
6. 6.True or false: a long and a short line is the symbol for a cell. (a) True (b) False
7. 7.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 7000 Ω resistor? (a) grey-violet-red (b) violet-black-red (c) violet-black-orange (d) violet-black-brown
8. 8.🌈 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
9. 9.🔐 Is it a good or a risky habit to share camera links? (a) good habit (b) risky habit
10. 10.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
11. 11.True or false: the ammeter measures current. (a) True (b) False
12. 12.Which of these mainly gives out light? (a) an exhaust fan (b) a night lamp (c) a water heater (d) an electric toy car
13. 13.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the glass (c) the switch (d) the base
14. 14.Which of these is true of a series circuit? (a) each gets the full volts (b) one out, the rest glow (c) many paths for current (d) bulbs share the voltage
15. 15.🔺 A current of 25 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
16. 16.Which of these has no microcontroller inside? (a) a digital alarm clock (b) a hand pump (c) a microwave oven (d) a smart watch
17. 17.🔁 What does a variable do in a program? (a) blinks an LED (b) measures light (c) joins two wires (d) stores a value
18. 18.🗺️ In an input → process → output plan, is “a soil moisture reading” the input, the process or the output? (a) output (b) process (c) input
19. 19.🧩 Which component beeps for an alarm? (a) buzzer (b) resistor (c) motor (d) LED
20. 20.🔺 A current of 40 mA flows when 4.8 V is joined across a resistor. What is its resistance (in ohms)?
21. 21.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
22. 22.🔍 Which is the odd one out? (a) an app-controlled bulb (b) a smart energy meter (c) a paper calendar (d) a Wi-Fi smart plug
23. 23.⚡ A 0.375 W device works on 1.5 V. What current does it take (in amperes)? =
24. 24.🔋 2 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
25. 25.🔗 Series or parallel circuit: “own switch for each bulb”? (a) series (b) parallel
26. 26.🌈 A resistor has the colour bands brown, green, red. What is its value (in ohms)?
27. 27.🧮 Two resistors in parallel give a total that is … (a) less than either one (b) always zero (c) their sum (d) more than either one
28. 28.True or false: if all wires are joined, the circuit is closed and current flows. (a) True (b) False
29. 29.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
30. 30.💡 A red LED uses 2 V and should get 20 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
31. 31.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
32. 32.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 100 ms }
    How many times does the LED blink in 3 seconds?
33. 33.True or false: a laptop runs one small program. (a) False (b) True
34. 34.🔺 A 1 V supply is joined across a 10 Ω resistor. What current flows (in amperes)? =
35. 35.⚠️ Is it safe to keep drinks far away? (a) safe (b) not safe
36. 36.⚠️ About how many volts do home sockets in India supply? (a) 230 V (b) 1.5 V (c) 12 V (d) 9 V
37. 37.🔋 What is a battery? (a) one single wire (b) two or more cells joined (c) a kind of bulb (d) a switch with a lid
38. 38.True or false: a transistor senses how bright it is. (a) True (b) False
39. 39.🔘 Which kind of switch stays where you flip it? (a) a push button (b) a toggle switch (c) a reed switch (d) a slide switch
40. 40.What does a slide switch do? (a) closes near a magnet (b) slides side to side (c) stays where you flip it (d) closes when tipped over

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