Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 968 · 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.True or false: to reuse one password is a good habit. (a) True (b) False
2. 2.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = R ÷ V (c) I = V × R (d) I = V + R
3. 3.🔺 A current of 3 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
4. 4.🔁 total = 0
   for i = 1 to 5 { total = total + i }
   What is total at the end?
5. 5.🔍 Which is the odd one out? (a) a steel spoon (b) a paper strip (c) an iron nail (d) a copper wire
6. 6.🔋 4 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)? =
7. 7.💡 2 identical bulbs are joined in series with a 6 V battery (ideal wires). How many volts does each bulb get? =
8. 8.🧾 A 1500 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
9. 9.🧮 Two equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
10. 10.True or false: on a cell, “the flat end” means the + (positive) end. (a) True (b) False
11. 11.🌐 How does a home IoT device usually send its data to the app? (a) by post (b) by shouting (c) over Wi-Fi (d) through a candle
12. 12.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 volt (c) 1 watt (d) 1 kilowatt-hour (kWh)
13. 13.🧮 Two equal 40 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
14. 14.🔺 A current of 2.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
15. 15.💡 4 identical bulbs are joined in parallel across a 9 V battery (ideal wires). How many volts does each bulb get? =
16. 16.🔘 Which kind of switch closes when tipped over? (a) a tilt switch (b) a reed switch (c) a toggle switch (d) a slide switch
17. 17.Which of these means the circuit is closed? (a) the loop is complete (b) the bulb is unscrewed (c) the switch is OFF (d) a cell is taken out
18. 18.Which of these means the circuit is open? (a) the loop is complete (b) all wires are joined (c) the switch is OFF (d) the switch is ON
19. 19.🔺 A current of 0.1 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
20. 20.True or false: to stop if a part gets hot is not safe. (a) True (b) False
21. 21.🔍 Which is the odd one out? (a) a traffic signal (b) a night lamp (c) an LED lamp (d) a rice cooker
22. 22.🔺 A current of 50 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
23. 23.🔁 total = 0
    for i = 1 to 8 { total = total + i }
    What is total at the end?
24. 24.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
25. 25.⏱️ loop forever { LED ON; wait 450 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 7 seconds?
26. 26.Which of these mainly gives out light? (a) a street light (b) a ceiling fan (c) a table fan (d) a siren
27. 27.🤖 Where does the board keep its program when the power is off? (a) the power LED (b) the USB cable (c) flash memory (d) the resistor
28. 28.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) switch (b) resistor (c) junction (d) battery
29. 29.True or false: to install software updates is a good habit. (a) False (b) True
30. 30.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 910 Ω resistor? (a) white-brown-red (b) white-brown-black (c) white-brown-brown (d) brown-white-brown
31. 31.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) ammeter (b) resistor (c) diode (d) battery
32. 32.🔋 Does an air conditioner give electricity or use electricity? (a) uses electricity (b) gives electricity
33. 33.🔺 A current of 2.5 A flows through a 12 Ω resistor. What is the voltage across it (in volts)? =
34. 34.⚠️ Is it safe to use small battery cells? (a) safe (b) not safe
35. 35.Which of these is a good habit? (a) accept every permission (b) post your live location (c) share only needed data (d) keep factory passwords
36. 36.🗺️ In an input → process → output plan, is “an alert on the phone” the input, the process or the output? (a) process (b) input (c) output
37. 37.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
38. 38.🤖 Does a bicycle bell usually have a microcontroller inside? (a) Yes (b) No
39. 39.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
40. 40.🔘 A bulb and a cell are joined through 5 switches on 5 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?

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