Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 326 · 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.🔺 A current of 20 mA flows when 4.4 V is joined across a resistor. What is its resistance (in ohms)?
2. 2.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) wire (b) capacitor (c) switch (d) voltmeter
3. 3.🔁 repeat 2 times { repeat 4 times { beep } }
   How many beeps are there?
4. 4.⚡ Which tiny particles drift along a metal wire to carry the current? (a) water drops (b) electrons (c) photons (d) dust particles
5. 5.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
6. 6.💡 3 identical bulbs are in parallel and each one takes 1 A. What total current (in amperes) comes from the battery? =
7. 7.🔍 Which is the odd one out? (a) touch a fallen wire (b) poke things in a socket (c) use small battery cells (d) use mains for a project
8. 8.📶 Digital or analog: many values in a range? (a) analog (b) digital
9. 9.⚠️ About how many volts do home sockets in India supply? (a) 1.5 V (b) 12 V (c) 230 V (d) 9 V
10. 10.🧩 Which component boosts a small signal? (a) thermistor (b) resistor (c) diode (d) transistor
11. 11.What does a toggle switch do? (a) stays where you flip it (b) slides side to side (c) springs back when let go (d) works only while pressed
12. 12.🔍 Which is the odd one out? (a) an LED lamp (b) a street light (c) an electric drill (d) a tube light
13. 13.🔘 Which kind of switch works only while pressed? (a) a tilt switch (b) a push button (c) a toggle switch (d) a reed switch
14. 14.Which drawing is the symbol for an ammeter? (a) two or more cell symbols (b) triangle, bar and arrows (c) triangle against a bar (d) a circle with A inside
15. 15.🔍 Which sensor would you use to close a window in rain? (a) a sound sensor (b) a light sensor (c) a rain sensor (d) a distance sensor
16. 16.💡 4 identical bulbs are joined in series with an 8 V battery (ideal wires). How many volts does each bulb get? =
17. 17.True or false: the ammeter measures current. (a) False (b) True
18. 18.⏱️ repeat 2 times { buzzer ON; wait 300 ms; buzzer OFF; wait 800 ms }
    How many milliseconds does this take in all?
19. 19.🔘 When a switch is ON, the circuit is … (a) broken (b) closed (c) open (d) cut
20. 20.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
21. 21.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) waits 500 seconds (c) turns the LED off (d) pauses for half a second
22. 22.🔍 Which is the odd one out? (a) a smart energy meter (b) an app-controlled bulb (c) a plain table fan (d) a fitness band with app
23. 23.Which of these is an insulator? (a) a copper wire (b) aluminium foil (c) a rubber band (d) a brass key
24. 24.⚡ A device works on 24 V and takes 0.25 A. What is its power (in watts)? =
25. 25.🗺️ In an input → process → output plan, is “the fan starts” the input, the process or the output? (a) output (b) process (c) input
26. 26.🤖 Does a plain wall switch usually have a microcontroller inside? (a) Yes (b) No
27. 27.Which of these is safe? (a) touch a fallen wire (b) stop if a part gets hot (c) fly a kite near wires (d) poke things in a socket
28. 28.⚡ 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
29. 29.💡 5 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 3 is taken out of its holder. Does bulb 4 glow? (a) Yes (b) No
30. 30.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) parallel (b) series
31. 31.Which job needs a temperature sensor? (a) keep an incubator warm (b) water a dry plant (c) make a parking alarm (d) measure classroom noise
32. 32.🔁 total = 0
    for i = 1 to 5 { total = total + i }
    What is total at the end?
33. 33.⚡ A device works on 9 V and takes 1.5 A. What is its power (in watts)? =
34. 34.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
35. 35.⚡ What does an electric iron mainly change electricity into? (a) light (b) heat (c) movement (d) sound
36. 36.🔁 repeat 2 times { repeat 6 times { beep } }
    How many beeps are there?
37. 37.True or false: to switch off empty rooms saves electricity. (a) True (b) False
38. 38.💡 In a series circuit, how many paths does the current have? (a) two (b) none (c) one (d) one for each bulb
39. 39.🧩 Which component senses how bright it is? (a) potentiometer (b) diode (c) fuse (d) LDR
40. 40.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a power source (d) a fuse

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