Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 15 · 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.🌐 Is a Wi-Fi smart plug an IoT device? (a) not an IoT device (b) an IoT device
2. 2.⚠️ Why must we never touch switches with wet hands? (a) it spoils the paint (b) water carries current (c) water makes it cold (d) it is just untidy
3. 3.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 300 ms }
   How many milliseconds does one blink (ON + OFF) take?
4. 4.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 100 (c) 60 (d) 1000
5. 5.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
6. 6.True or false: a microwave oven usually has a microcontroller inside. (a) False (b) True
7. 7.Which of these uses electricity? (a) a solar panel (b) a refrigerator (c) a cell (d) a wind turbine
8. 8.🌈 In the resistor colour code, which number does brown stand for?
9. 9.🔋 5 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)? =
10. 10.⚠️ About how many volts do home sockets in India supply? (a) 12 V (b) 230 V (c) 9 V (d) 1.5 V
11. 11.🤖 if (temperature > 35) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 35 °C. What is shown? (a) Hot (b) Warm (c) Cool
12. 12.📶 Digital or analog: how loud a sound is? (a) digital (b) analog
13. 13.🔺 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
14. 14.⏱️ loop forever { LED ON; wait 500 ms; LED OFF; wait 1500 ms }
    How many times does the LED blink in 18 seconds?
15. 15.🔌 A gap of dry air between two wires acts as … (a) a switch that is ON (b) an insulator (c) a cell (d) a conductor
16. 16.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
17. 17.🔁 count = 2
    repeat 5 times { count = count + 8 }
    What is count at the end?
18. 18.🔋 What is a battery? (a) a switch with a lid (b) one single wire (c) a kind of bulb (d) two or more cells joined
19. 19.🗺️ In an input → process → output plan, is “count button presses” the input, the process or the output? (a) process (b) output (c) input
20. 20.True or false: on an LED, the longer leg is the cathode (−). (a) False (b) True
21. 21.Which of these is not safe? (a) use small battery cells (b) keep drinks far away (c) stay away from pylons (d) throw cells in a fire
22. 22.True or false: a traffic signal mainly gives out heat. (a) False (b) True
23. 23.🔗 Series or parallel circuit: “one out, the rest glow”? (a) series (b) parallel
24. 24.🔍 Which is the odd one out? (a) fly a kite near wires (b) stop if a part gets hot (c) dry your hands first (d) build with an adult near
25. 25.🗺️ In an input → process → output plan, is “a buzzer beeps” the input, the process or the output? (a) input (b) process (c) output
26. 26.True or false: a laptop uses very little power. (a) False (b) True
27. 27.True or false: “a soil moisture reading” is the input. (a) True (b) False
28. 28.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) let strangers use it (b) tell it your passwords (c) mute it when not in use (d) put it in the bathroom
29. 29.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the base (b) the glass (c) the switch (d) the filament
30. 30.True or false: the ammeter measures voltage. (a) True (b) False
31. 31.True or false: if the switch is ON, the circuit is open and no current flows. (a) True (b) False
32. 32.💡 2 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?
33. 33.🤖 Microcontroller or laptop: which one has a built-in keyboard? (a) microcontroller (b) laptop
34. 34.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) bulb (b) junction (c) switch (d) battery
35. 35.🔌 Is aluminium foil a conductor or an insulator? (a) an insulator (b) a conductor
36. 36.🤖 if (temperature > 35) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 36 °C. What is shown? (a) Hot (b) Warm (c) Cool
37. 37.Which job needs a motor? (a) spin a robot’s wheels (b) turn to an exact angle (c) open a gate to 90° (d) show the temperature
38. 38.🔺 A current of 2 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
39. 39.🔺 A current of 2 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
40. 40.🔁 total = 0
    for i = 1 to 3 { total = total + i }
    What is total at the end?

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids