Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 410 · 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.🤖 if (temperature > 32) { fan ON } else { fan OFF }
   The temperature sensor reads 33 °C. What happens? (a) fan OFF (b) fan ON
2. 2.🧮 Resistors of 68 Ω, 150 Ω, 33 Ω and 330 Ω are joined in series. What is the total resistance (in ohms)?
3. 3.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = V + I (c) P = V × I (d) P = I ÷ V
4. 4.🧾 A 500 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
5. 5.🔺 A current of 3 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
6. 6.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 19 Ω resistor? (a) white-brown-black (b) red-white-black (c) brown-white-black (d) brown-white-brown
7. 7.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) capacitor (b) cell (c) junction (d) battery
8. 8.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
   set pin 7 LOW
   set pin 8 LOW
   Is the LED ON or OFF at the end? (a) ON (b) OFF
9. 9.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) in parallel (c) by Wi-Fi (d) in series
10. 10.True or false: to share only needed data is a risky habit. (a) True (b) False
11. 11.🔺 A current of 0.2 A flows through a 12 Ω resistor. What is the voltage across it (in volts)? =
12. 12.🗺️ In an input → process → output plan, is “an LED lights up” the input, the process or the output? (a) input (b) output (c) process
13. 13.Which of these is measured in volts (V)? (a) power (b) energy used each second (c) the push of a cell (d) the flow of charge
14. 14.📏 In the water-pipe picture of a circuit, voltage is like … (a) the water tank lid (b) the water pressure (c) the pipe colour (d) the tap handle
15. 15.True or false: on a cell, “usually the red wire” means the + (positive) end. (a) True (b) False
16. 16.Which drawing is the symbol for a bulb? (a) a long and a short line (b) a circle with a cross (c) one tall, one short bar (d) many long-short pairs
17. 17.🔍 Which is the odd one out? (a) a plain wall switch (b) a smart energy meter (c) a Wi-Fi doorbell camera (d) a Wi-Fi weather station
18. 18.🔗 Series or parallel circuit: “many paths for current”? (a) parallel (b) series
19. 19.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 400 ms }
    How many times does the LED blink in 5 seconds?
20. 20.💡 Why is house wiring done in parallel? (a) so all go off together (b) to make bulbs dim (c) each gets full voltage (d) to save copper only
21. 21.🔍 Which sensor would you use to measure classroom noise? (a) a distance sensor (b) a sound sensor (c) a motion sensor (d) a soil moisture sensor
22. 22.True or false: to switch on with a clap, use a distance sensor. (a) True (b) False
23. 23.🔁 count = 8
    repeat 4 times { count = count + 6 }
    What is count at the end?
24. 24.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) never (c) when both are OFF (d) when both are ON
25. 25.True or false: to share the Wi-Fi key is a risky habit. (a) True (b) False
26. 26.⏱️ loop forever { LED ON; wait 600 ms; LED OFF; wait 950 ms }
    How many milliseconds does one blink (ON + OFF) take?
27. 27.🧮 Resistors of 150 Ω, 22 Ω, 330 Ω and 150 Ω are joined in series. What is the total resistance (in ohms)?
28. 28.⚡ A device works on 24 V and takes 0.5 A. What is its power (in watts)? =
29. 29.True or false: “a break stops every bulb” is true of a series circuit. (a) True (b) False
30. 30.⚡ A 2.25 W device works on 9 V. What current does it take (in amperes)? =
31. 31.⚠️ Which power source should children use for electronics projects? (a) a wall socket (b) an inverter socket (c) a small battery pack (d) a mains extension board
32. 32.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the reset button (b) the voltage regulator (c) the USB port (d) the pins
33. 33.⚡ Power tells us … (a) the length of a wire (b) the colour of light (c) the size of a cell (d) energy used each second
34. 34.Which of these is true of a series circuit? (a) one out, the rest glow (b) bulbs share the voltage (c) many paths for current (d) each gets the full volts
35. 35.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
36. 36.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 watt (c) 1 ampere (d) 1 volt
37. 37.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
38. 38.True or false: “a soil moisture reading” is the output. (a) False (b) True
39. 39.What does a tilt switch do? (a) slides side to side (b) stays where you flip it (c) closes when tipped over (d) flips up or down
40. 40.⚠️ Is it safe to use a cable with cuts? (a) safe (b) not safe

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