Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 626 · 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.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
2. 2.What does a capacitor do? (a) senses how hot it is (b) senses how bright it is (c) makes a beeping sound (d) stores a little charge
3. 3.⚡ What does a torch mainly change electricity into? (a) movement (b) heat (c) sound (d) light
4. 4.🔍 Which is the odd one out? (a) a fitness band with app (b) a plain table fan (c) a Wi-Fi weather station (d) an app-controlled bulb
5. 5.🔁 What must there be for a current to flow? (a) a complete loop (b) a plastic gap (c) one loose end (d) a broken path
6. 6.🌈 Which band is read first on a resistor? (a) the widest gap (b) the one nearest an end (c) any band (d) the gold band
7. 7.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
8. 8.True or false: a metal paper clip is an insulator. (a) False (b) True
9. 9.Which of these is a risky habit? (a) change default passwords (b) keep factory passwords (c) read app permissions (d) set up with a parent
10. 10.True or false: if a cell is taken out, the circuit is closed and current flows. (a) False (b) True
11. 11.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they get dimmer (c) they keep glowing (d) they all go out
12. 12.📏 How many ohms (Ω) is 7.8 kΩ?
13. 13.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 60 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
14. 14.🔋 A 9 V battery and four 1.5 V cells are joined in series, all facing the same way. What is the total voltage (in volts)? =
15. 15.⚡ Power tells us … (a) the colour of light (b) energy used each second (c) the length of a wire (d) the size of a cell
16. 16.Which of these is measured in ohms (Ω)? (a) the flow of charge (b) resistance (c) power (d) the push of a cell
17. 17.🤖 Does a bicycle bell usually have a microcontroller inside? (a) Yes (b) No
18. 18.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) nothing at all (d) the final price
19. 19.Which job needs a buzzer? (a) beep an alarm (b) spin a robot’s wheels (c) turn to an exact angle (d) open a gate to 90°
20. 20.Which of these is an output? (a) a turning knob (b) a push button (c) a water pump (d) a temperature sensor
21. 21.💡 Why is house wiring done in parallel? (a) to make bulbs dim (b) each gets full voltage (c) to save copper only (d) so all go off together
22. 22.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 410 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
23. 23.🔺 A current of 50 mA flows when 10 V is joined across a resistor. What is its resistance (in ohms)?
24. 24.🤖 Which is a safe power source for a beginner microcontroller board? (a) bare mains wires (b) USB or a 9 V battery (c) a 230 V cable (d) a wall socket directly
25. 25.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 4 hours. How many watt-hours (Wh) are saved?
26. 26.⚙️ What is an actuator? (a) a program (b) a battery (c) a sensor (d) an output that acts
27. 27.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
28. 28.🔍 Which is the odd one out? (a) a plain table fan (b) a battery torch (c) a smart energy meter (d) a plain wall switch
29. 29.📶 How many states can a digital pin have? (a) one (b) a thousand (c) ten (d) two
30. 30.🤖 Does a microwave oven usually have a microcontroller inside? (a) Yes (b) No
31. 31.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a wooden stick. Does the bulb glow? (a) No (b) Yes
32. 32.True or false: on an LED, the longer leg is the cathode (−). (a) True (b) False
33. 33.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
34. 34.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is OFF and C is ON. Does the bulb glow? (a) No (b) Yes
35. 35.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 530 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
36. 36.True or false: a microcontroller runs many apps at once. (a) True (b) False
37. 37.What does a diode do? (a) senses how bright it is (b) turns a fan or wheels (c) lets current go one way (d) makes a beeping sound
38. 38.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
39. 39.True or false: triangle against a bar is the symbol for a diode. (a) True (b) False
40. 40.🔍 Which is the odd one out? (a) an LED lamp (b) a night lamp (c) a street light (d) an electric toy car

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