Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 44 · 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.What does a slide switch do? (a) stays where you flip it (b) slides side to side (c) springs back when let go (d) flips up or down
2. 2.Which of these is a good habit? (a) post your live location (b) reuse one password (c) tap unknown app links (d) change default passwords
3. 3.🔍 Which is the odd one out? (a) the fan starts (b) decide if soil is dry (c) check if temp > 30 (d) count button presses
4. 4.True or false: a smart watch has no microcontroller inside. (a) False (b) True
5. 5.🔌 Is a copper wire a conductor or an insulator? (a) a conductor (b) an insulator
6. 6.True or false: a laptop has no screen of its own. (a) False (b) True
7. 7.🔢 To get a sensor reading onto a phone, which is the LAST step? (a) the app shows it (b) it is sent by Wi-Fi (c) the sensor measures (d) the board reads it
8. 8.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a display (c) a servo motor (d) a motor
9. 9.Which of these mainly makes movement? (a) a night lamp (b) a school bell (c) a ceiling fan (d) a room heater
10. 10.🧮 Resistors of 68 Ω, 20 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
11. 11.🔁 count = 4
    while (count < 16) { count = count + 3 }
    How many times does the loop run?
12. 12.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) only when both are ON (b) never (c) only when both are OFF (d) when either is ON
13. 13.🔁 repeat 3 times { repeat 5 times { beep } }
    How many beeps are there?
14. 14.Which of these usually has a microcontroller inside? (a) a hand pump (b) a TV remote (c) a bicycle bell (d) a candle
15. 15.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) the longer line (c) both lines (d) neither line
16. 16.True or false: a slide switch slides side to side. (a) True (b) False
17. 17.🧮 Resistors of 50 Ω, 10 Ω and 68 Ω are joined in series. What is the total resistance (in ohms)?
18. 18.Which of these is true of a series circuit? (a) each gets the full volts (b) many paths for current (c) a break stops every bulb (d) own switch for each bulb
19. 19.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = R ÷ V (c) I = V × R (d) I = V + R
20. 20.🔌 Is a motion sensor an input or an output for a microcontroller? (a) input (b) output
21. 21.🔌 Is a sound sensor an input or an output for a microcontroller? (a) input (b) output
22. 22.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
23. 23.True or false: voltage is measured in watts (W). (a) False (b) True
24. 24.⚡ Power tells us … (a) the colour of light (b) the size of a cell (c) energy used each second (d) the length of a wire
25. 25.💡 6 identical bulbs are in parallel and each one takes 1.5 A. What total current (in amperes) comes from the battery? =
26. 26.⏱️ repeat 9 times { buzzer ON; wait 400 ms; buzzer OFF; wait 1000 ms }
    How many milliseconds does this take in all?
27. 27.💡 Why does an LED need a resistor in series? (a) to store charge (b) to change its colour (c) to limit the current (d) to make it brighter
28. 28.Which of these mainly makes movement? (a) a mixer grinder (b) a traffic signal (c) a room heater (d) a torch
29. 29.True or false: “a light level reading” is the input. (a) True (b) False
30. 30.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) put it in the bathroom (d) mute it when not in use
31. 31.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
32. 32.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 27 Ω resistor? (a) orange-violet-black (b) red-violet-brown (c) red-violet-black (d) violet-red-black
33. 33.🔺 A 23.5 V supply is joined across a 470 Ω resistor. What current flows (in milliamperes, mA)?
34. 34.📏 Which unit measures energy used each second? (a) ampere (A) (b) volt (V) (c) watt (W) (d) ohm (Ω)
35. 35.🔺 In the V-I-R triangle, how do we find R? (a) R = V ÷ I (b) R = V + I (c) R = V × I (d) R = I ÷ V
36. 36.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) when both are ON (c) when both are OFF (d) never
37. 37.🔍 Which is the odd one out? (a) an exhaust fan (b) a tube light (c) a torch (d) an LED lamp
38. 38.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) gets bigger (c) gets smaller (d) stays the same
39. 39.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a capacitor (c) a resistor (d) a diode
40. 40.🔢 To run one loop of a plant-watering program, which comes first: “switch the pump on/off” or “read the soil sensor”? (a) switch the pump on/off (b) read the soil sensor

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