Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 431 · 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 of these is measured in ohms (Ω)? (a) resistance (b) current (c) power (d) voltage
2. 2.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a plastic ruler. Does the bulb glow? (a) Yes (b) No
3. 3.💡 5 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
4. 4.🧾 Which lamp gives the same light for the least power? (a) an LED lamp (b) a filament bulb (c) a candle (d) an oil lamp
5. 5.⏱️ loop forever { LED ON; wait 850 ms; LED OFF; wait 150 ms }
   How many times does the LED blink in 10 seconds?
6. 6.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 8 HIGH
   set pin 7 HIGH
   set pin 7 HIGH
   set pin 8 HIGH
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) ON (b) OFF
7. 7.💡 An LED is joined to a 5 V battery through a 330 Ω resistor; its long leg goes to the − side and its short leg to the + side. What happens? (a) lights up (b) does not light (c) may burn out
8. 8.🔺 A 10 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =
9. 9.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
10. 10.Which job needs a buzzer? (a) open a gate to 90° (b) beep an alarm (c) move water to plants (d) turn to an exact angle
11. 11.True or false: to use mains for a project is not safe. (a) False (b) True
12. 12.🔋 8 identical 1.5 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
13. 13.📶 How many states can a digital pin have? (a) two (b) ten (c) one (d) a thousand
14. 14.🤖 “if (A AND B)” is true when … (a) both A and B are true (b) both are false (c) only B is true (d) only A is true
15. 15.🧭 Which part of a microcontroller board runs the program? (a) the power LED (b) the USB port (c) the reset button (d) the main chip
16. 16.True or false: a toy robot has no microcontroller inside. (a) False (b) True
17. 17.📏 How many milliamperes (mA) is 2.83 A?
18. 18.💡 2 identical bulbs are joined in parallel across a 9 V battery (ideal wires). How many volts does each bulb get? =
19. 19.Which of these is the process? (a) the pump turns on (b) a buzzer beeps (c) compare with a limit (d) a temperature reading
20. 20.🌐 What does IoT stand for? (a) Input of Tools (b) Internet of Things (c) Inside of Toys (d) Internet of Talk
21. 21.Which job needs a soil moisture sensor? (a) switch on with a clap (b) open blinds at sunrise (c) measure classroom noise (d) water a dry plant
22. 22.🔁 repeat 4 times { repeat 4 times { beep } }
    How many beeps are there?
23. 23.Which of these usually has a microcontroller inside? (a) a wind-up toy (b) a toy robot (c) a candle (d) a hand pump
24. 24.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
25. 25.🧮 A 1.6 V battery is joined to 6 Ω and 10 Ω resistors in series. What current flows (in amperes)? =
26. 26.Which of these is not safe? (a) build with an adult near (b) stay away from pylons (c) poke things in a socket (d) use small battery cells
27. 27.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a motion sensor (c) a temperature sensor (d) a gas sensor
28. 28.🔍 Which is the odd one out? (a) a steel spoon (b) an iron nail (c) a safety pin (d) a woollen thread
29. 29.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
30. 30.🔺 In the V-I-R triangle, how do we find I? (a) I = R ÷ V (b) I = V × R (c) I = V + R (d) I = V ÷ R
31. 31.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) neither line (d) both lines
32. 32.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) quick and clear for all (c) symbols are heavier (d) to hide the circuit
33. 33.🧩 Which component makes things spin? (a) resistor (b) capacitor (c) diode (d) motor
34. 34.What does the Wi-Fi link do? (a) carries the data (b) reads values, decides (c) stores data online (d) measures the real world
35. 35.Which of these mainly gives out light? (a) a tube light (b) an electric iron (c) a mixer grinder (d) a siren
36. 36.True or false: to warn of a gas leak, use a distance sensor. (a) True (b) False
37. 37.🌐 A weather station sends one reading every 20 seconds. How many readings does it send in 10 minutes?
38. 38.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) wire (b) diode (c) voltmeter (d) capacitor
39. 39.📏 How many amperes (A) is 1430 mA? =
40. 40.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?

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