Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 72 · 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 touch a fallen wire is safe. (a) False (b) True
2. 2.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 7 HIGH
   set pin 7 LOW
   set pin 8 LOW
   set pin 7 LOW
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) ON (b) OFF
3. 3.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) False (b) True
4. 4.Which of these means the circuit is closed? (a) a wire is cut (b) the switch is ON (c) the bulb is unscrewed (d) a wire has come loose
5. 5.🤖 if (temperature > 37) { show “Hot” } else if (temperature > 19) { show “Warm” } else { show “Cool” }
   The temperature is 20 °C. What is shown? (a) Hot (b) Cool (c) Warm
6. 6.🔁 total = 0
   for i = 1 to 5 { total = total + i }
   What is total at the end?
7. 7.🧮 A 1.6 V battery is joined to 2 Ω and 6 Ω resistors in series. What current flows (in amperes)? =
8. 8.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
   set pin 8 LOW
   set pin 7 LOW
   set pin 8 HIGH
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) OFF (b) ON
9. 9.🔍 Which is the odd one out? (a) open a phone charger (b) climb an electric pole (c) use mains for a project (d) stay away from pylons
10. 10.Which of these saves electricity? (a) run fans in empty rooms (b) iron one shirt at a time (c) leave fridge door open (d) switch off empty rooms
11. 11.🔌 Is a servo motor an input or an output for a microcontroller? (a) output (b) input
12. 12.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
13. 13.🤖 if (temperature > 38) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
    The temperature is 11 °C. What is shown? (a) Hot (b) Warm (c) Cool
14. 14.🔍 Which is the odd one out? (a) a plain table fan (b) a paper calendar (c) a smart energy meter (d) a plain wall switch
15. 15.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
16. 16.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) never (b) when either is ON (c) only when both are ON (d) only when both are OFF
17. 17.⚡ Which formula gives electric power? (a) P = V × I (b) P = I ÷ V (c) P = V + I (d) P = V ÷ I
18. 18.True or false: one tall, one short bar is the symbol for a wire. (a) True (b) False
19. 19.🧩 Which part changes electrical energy into sound? (a) a capacitor (b) a diode (c) a resistor (d) a buzzer
20. 20.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 600 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
21. 21.⏱️ How many milliseconds is a wait of 3.3 seconds?
22. 22.Which of these is the process? (a) an LED lights up (b) a button press (c) decide if soil is dry (d) the pump turns on
23. 23.🔺 A current of 25 mA flows through a 470 Ω resistor. What is the voltage across it (in volts)? =
24. 24.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
25. 25.🔌 Is a steel spoon a conductor or an insulator? (a) an insulator (b) a conductor
26. 26.📶 A pin that reads a push button is set as … (a) a battery (b) an output (c) an input (d) a resistor
27. 27.⚡ What does an electric drill mainly change electricity into? (a) sound (b) movement (c) heat (d) light
28. 28.📏 Which unit measures resistance? (a) volt (V) (b) watt (W) (c) ampere (A) (d) ohm (Ω)
29. 29.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
30. 30.🌈 A resistor has the colour bands grey, grey, red. What is its value (in ohms)?
31. 31.Which of these is a conductor? (a) a rubber eraser (b) a steel coin (c) a wooden stick (d) a glass marble
32. 32.🧮 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
33. 33.🔍 Which is the odd one out? (a) the pump turns on (b) a button press (c) a buzzer beeps (d) an LED lights up
34. 34.Which job is done by the main chip? (a) brings power and code (b) runs the program (c) shows the board is on (d) keeps the voltage steady
35. 35.🔗 Series or parallel circuit: “each gets the full volts”? (a) parallel (b) series
36. 36.🔌 Is a wooden stick a conductor or an insulator? (a) a conductor (b) an insulator
37. 37.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) ON (b) OFF
38. 38.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 700 ms }
    How many milliseconds does one blink (ON + OFF) take?
39. 39.🔁 count = 0
    while (count < 24) { count = count + 4 }
    How many times does the loop run?
40. 40.🔋 What should you do with used-up cells? (a) throw them in a fire (b) bury them in soil (c) cut them open (d) give them for recycling

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