Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 733 · 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.⏱️ loop forever { LED ON; wait 850 ms; LED OFF; wait 450 ms }
   How many milliseconds does one blink (ON + OFF) take?
2. 2.🤖 if (temperature > 30) { fan ON } else { fan OFF }
   The temperature sensor reads 31 °C. What happens? (a) fan OFF (b) fan ON
3. 3.True or false: current is measured in watts (W). (a) False (b) True
4. 4.Which drawing is the symbol for a switch? (a) a line lifted at a gap (b) two or more cell symbols (c) two equal parallel lines (d) triangle, bar and arrows
5. 5.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = V ÷ I (c) R = I ÷ V (d) R = V + I
6. 6.🔍 Which is the odd one out? (a) turn off unused gadgets (b) log out of shared phones (c) keep factory passwords (d) share only needed data
7. 7.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
8. 8.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 200 ms }
   How many times does the LED blink in 2 seconds?
9. 9.Which of these is not safe? (a) build with an adult near (b) fly kites in open fields (c) poke things in a socket (d) stay away from pylons
10. 10.📏 In the water-pipe picture of a circuit, resistance is like … (a) a bigger tank (b) the water pressure (c) the flow of water (d) a narrow pipe
11. 11.🔐 Privacy for a smart device means controlling … (a) how loud it beeps (b) who can see your data (c) its battery size (d) its colour
12. 12.⚠️ Is it safe to open a phone charger? (a) not safe (b) safe
13. 13.🔋 How many volts does one ordinary torch cell give? (a) 230 V (b) 1.5 V (c) 0.5 V (d) 15 V
14. 14.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
15. 15.🔍 Which is the odd one out? (a) a temperature reading (b) decide if soil is dry (c) count button presses (d) check if temp > 30
16. 16.🔁 total = 0
    for i = 1 to 3 { total = total + i }
    What is total at the end?
17. 17.Which job is done by the pins? (a) keeps the voltage steady (b) runs the program (c) connect sensors and LEDs (d) shows the board is on
18. 18.🧭 Which part of a microcontroller board brings power and code? (a) the reset button (b) the USB port (c) the voltage regulator (d) the main chip
19. 19.🔌 Is a brass key a conductor or an insulator? (a) an insulator (b) a conductor
20. 20.🔺 In the V-I-R triangle, how do we find V? (a) V = I ÷ R (b) V = I + R (c) V = R ÷ I (d) V = I × R
21. 21.🔺 A current of 2 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
22. 22.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 3 V supply. What current flows (in mA)?
23. 23.⏱️ repeat 2 times { buzzer ON; wait 900 ms; buzzer OFF; wait 900 ms }
    How many milliseconds does this take in all?
24. 24.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 1 glow? (a) No (b) Yes
25. 25.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a display (c) an LED (d) a motor
26. 26.True or false: a laptop needs much more power. (a) False (b) True
27. 27.⚡ 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
28. 28.🔐 Is it a good or a risky habit to share only needed data? (a) risky habit (b) good habit
29. 29.🤖 Microcontroller or laptop: which one uses very little power? (a) microcontroller (b) laptop
30. 30.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a resistor (c) a diode (d) a capacitor
31. 31.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) series (b) parallel
32. 32.True or false: a safety pin is a conductor. (a) True (b) False
33. 33.🔺 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
34. 34.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
35. 35.Which of these is true of a parallel circuit? (a) a break stops every bulb (b) a single current path (c) many paths for current (d) one bulb out, all go out
36. 36.🤖 When the main loop of a microcontroller program ends, what happens? (a) it stops forever (b) it deletes itself (c) the board breaks (d) it starts again
37. 37.💡 An LED is joined to a 6 V battery with no 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
38. 38.🔋 5 identical 1.2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
39. 39.🔺 A 3 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
40. 40.⚡ What do we call a flow of electric charge through a wire? (a) a magnet (b) electric current (c) friction (d) sound

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