Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 346 · 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.🌐 In an IoT system, which part shows data to you? (a) phone app (b) actuator (c) microcontroller (d) sensor
2. 2.Which of these is measured in volts (V)? (a) the push of a cell (b) how much a part resists (c) current (d) the flow of charge
3. 3.True or false: a digital alarm clock has no microcontroller inside. (a) True (b) False
4. 4.Which drawing is the symbol for a bulb? (a) a circle with a cross (b) a plain rectangle (c) a circle with V inside (d) a circle with A inside
5. 5.True or false: “a tilt switch: on or off” is a digital signal. (a) True (b) False
6. 6.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
7. 7.🔍 Which is the odd one out? (a) a rubber band (b) a cotton thread (c) a plastic ruler (d) a safety pin
8. 8.💡 4 identical bulbs are in parallel and each bulb has its own switch on its path. 1 of the switches is OFF and the rest are ON. How many bulbs glow?
9. 9.🔺 A current of 50 mA flows when 25 V is joined across a resistor. What is its resistance (in ohms)?
10. 10.True or false: “a door: open or shut” is an analog signal. (a) True (b) False
11. 11.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 50 % (c) 25 % (d) 5 %
12. 12.True or false: a circle with M inside is the symbol for a motor. (a) False (b) True
13. 13.🔺 A current of 0.1 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
14. 14.🔁 count = 1
    repeat 2 times { count = count + 2 }
    What is count at the end?
15. 15.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
16. 16.🔍 Which is the odd one out? (a) climb an electric pole (b) open a phone charger (c) take cells out after use (d) throw cells in a fire
17. 17.⚡ A device works on 1.5 V and takes 1.5 A. What is its power (in watts)? =
18. 18.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the main chip (b) the voltage regulator (c) the reset button (d) the pins
19. 19.💡 4 identical bulbs are joined in series with a 12 V battery (ideal wires). How many volts does each bulb get? =
20. 20.Which of these is a risky habit? (a) change default passwords (b) set up with a parent (c) ignore update messages (d) cover unused cameras
21. 21.True or false: “how bright a room is” is a digital signal. (a) True (b) False
22. 22.Which of these is not safe? (a) keep drinks far away (b) build with an adult near (c) use small battery cells (d) use a cable with cuts
23. 23.Which of these is the process? (a) decide if soil is dry (b) a temperature reading (c) a light level reading (d) a buzzer beeps
24. 24.⚡ A device works on 24 V and takes 0.5 A. What is its power (in watts)? =
25. 25.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
26. 26.True or false: “used in house wiring” is true of a series circuit. (a) True (b) False
27. 27.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 300 ms }
    How many milliseconds does one blink (ON + OFF) take?
28. 28.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) a power source (d) an input
29. 29.Which of these is an IoT device? (a) a battery torch (b) a smart energy meter (c) a wind-up clock (d) a plain table fan
30. 30.Which job needs a sound sensor? (a) switch on with a clap (b) start a fan when hot (c) close a window in rain (d) stop a robot near walls
31. 31.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) both parts (c) neither part (d) the if part
32. 32.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 25 °C. What is shown? (a) Warm (b) Cool (c) Hot
33. 33.Which job needs a motion sensor? (a) keep an incubator warm (b) spot someone walking in (c) start a fan when hot (d) measure classroom noise
34. 34.True or false: a buzzer beeps for an alarm. (a) False (b) True
35. 35.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 19) { show “Warm” } else { show “Cool” }
    The temperature is 30 °C. What is shown? (a) Hot (b) Cool (c) Warm
36. 36.🔍 Which is the odd one out? (a) an iron nail (b) a steel spoon (c) a steel coin (d) a plastic ruler
37. 37.⚡ A device works on 9 V and takes 1.5 A. What is its power (in watts)? =
38. 38.⏱️ A program says “wait 6250 ms”. How many seconds is that? =
39. 39.🌐 What does IoT stand for? (a) Internet of Things (b) Input of Tools (c) Inside of Toys (d) Internet of Talk
40. 40.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) + (positive) (b) − (negative)

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