Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 817 · 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 water pump an input or an output for a microcontroller? (a) output (b) input
2. 2.True or false: “HIGH or LOW only” is a digital signal. (a) True (b) False
3. 3.⚡ A 12 W device works on 12 V. What current does it take (in amperes)? =
4. 4.📏 How many amperes (A) is 40 mA? =
5. 5.Which job is done by the pins? (a) keeps the voltage steady (b) connect sensors and LEDs (c) brings power and code (d) restarts the program
6. 6.🔺 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
7. 7.Which of these is measured in volts (V)? (a) power (b) voltage (c) current (d) how much a part resists
8. 8.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is ON and B is ON. Does the bulb glow? (a) Yes (b) No
9. 9.🔍 Which is the odd one out? (a) a night lamp (b) a torch (c) an electric iron (d) a traffic signal
10. 10.🔍 Which is the odd one out? (a) post your live location (b) cover unused cameras (c) ignore update messages (d) reuse one password
11. 11.📏 How many milliamperes (mA) is 2.57 A?
12. 12.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
13. 13.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a safety pin across the gap. Does the bulb glow? (a) No (b) Yes
14. 14.🧾 A 500 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
15. 15.🧾 A family uses 170 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
16. 16.Which of these is not safe? (a) build with an adult near (b) use mains for a project (c) stay away from pylons (d) keep drinks far away
17. 17.🔁 count = 8
    repeat 6 times { count = count + 7 }
    What is count at the end?
18. 18.Which of these is an insulator? (a) a dry cork (b) a safety pin (c) a copper wire (d) a metal paper clip
19. 19.💡 An LED is joined to a 3 V battery through a 220 Ω resistor; its long leg goes to the − side and its short leg to the + side. What happens? (a) lights up (b) may burn out (c) does not light
20. 20.True or false: “bulbs share the voltage” is true of a series circuit. (a) True (b) False
21. 21.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is OFF and B is OFF. Does the bulb glow? (a) Yes (b) No
22. 22.⚡ What does an LED lamp mainly change electricity into? (a) sound (b) movement (c) light (d) heat
23. 23.🔍 Which sensor would you use to switch on lamps at dusk? (a) a motion sensor (b) a light sensor (c) a temperature sensor (d) a rain sensor
24. 24.Which of these wastes electricity? (a) use daylight to read (b) iron one shirt at a time (c) set the AC to 24 °C (d) use LED lamps
25. 25.🔺 A current of 1 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
26. 26.True or false: “a single current path” is true of a parallel circuit. (a) False (b) True
27. 27.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets bigger (b) stays the same (c) gets smaller (d) becomes zero
28. 28.True or false: a toggle switch flips up or down. (a) True (b) False
29. 29.🔺 A current of 0.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
30. 30.💡 An LED is joined to a 6 V battery through a 470 Ω 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
31. 31.⏱️ repeat 6 times { buzzer ON; wait 400 ms; buzzer OFF; wait 100 ms }
    How many milliseconds does this take in all?
32. 32.🔐 Which is the strongest password for a home smart camera? (a) Tiger#Lamp42!Moon (b) admin (c) 123456 (d) password
33. 33.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
34. 34.🔢 To run one loop of a plant-watering program, which comes first: “switch the pump on/off” or “compare with the limit”? (a) compare with the limit (b) switch the pump on/off
35. 35.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) a parallel circuit (b) an open circuit (c) a safe circuit (d) a short circuit
36. 36.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
37. 37.True or false: a digital thermometer has no microcontroller inside. (a) False (b) True
38. 38.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 8 HIGH
    set pin 8 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
39. 39.Which of these has no microcontroller inside? (a) a smart watch (b) a candle (c) a toy robot (d) a microwave oven
40. 40.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) ask a parent first (b) post it online (c) share it with friends (d) type it all in

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