Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 871 · 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.🏠 Which is a smart-home example? (a) a printed map (b) a candle in a jar (c) a hand fan (d) lights on from an app
2. 2.🧭 Which part of a microcontroller board keeps the voltage steady? (a) the voltage regulator (b) the reset button (c) the power LED (d) the main chip
3. 3.⚡ What does an LED lamp mainly change electricity into? (a) sound (b) movement (c) light (d) heat
4. 4.🔋 2 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
5. 5.🔋 Does a washing machine give electricity or use electricity? (a) uses electricity (b) gives electricity
6. 6.🧾 A family uses 100 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
7. 7.Which job needs a gas sensor? (a) keep an incubator warm (b) switch on with a clap (c) spot someone walking in (d) warn of a gas leak
8. 8.Which of these is a risky habit? (a) turn off unused gadgets (b) log out of shared phones (c) change default passwords (d) share the Wi-Fi key
9. 9.🤖 if (moisture < 50) { pump ON } else { pump OFF }
   The soil moisture sensor reads 68 %. What happens? (a) pump ON (b) pump OFF
10. 10.What does a tilt switch do? (a) closes when tipped over (b) flips up or down (c) works only while pressed (d) stays where you flip it
11. 11.True or false: “a single current path” is true of a series circuit. (a) True (b) False
12. 12.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is ON, B is ON and C is ON. Does the bulb glow? (a) Yes (b) No
13. 13.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) the else part (c) both parts (d) the if part
14. 14.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
15. 15.🔺 A current of 0.5 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
16. 16.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the longer line (d) the shorter line
17. 17.Which of these saves electricity? (a) leave the TV on standby (b) unplug idle chargers (c) iron one shirt at a time (d) run fans in empty rooms
18. 18.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
19. 19.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they all go out (c) they keep glowing (d) they explode
20. 20.True or false: “a buzzer beeps” is the output. (a) False (b) True
21. 21.🔺 A current of 20 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
22. 22.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False
23. 23.⚙️ Which actuator would you use to show a status light? (a) a display (b) a servo motor (c) a motor (d) an LED
24. 24.🔁 x = 2
    repeat 4 times { x = x × 2 }
    What is x at the end?
25. 25.True or false: a toy robot has no microcontroller inside. (a) False (b) True
26. 26.🔦 A circuit has a used-up (dead) 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 brass key. Does the bulb glow? (a) Yes (b) No
27. 27.💡 5 identical bulbs are joined in series with a 15 V battery (ideal wires). How many volts does each bulb get? =
28. 28.🔍 Which is the odd one out? (a) tap unknown app links (b) cover unused cameras (c) ignore update messages (d) share camera links
29. 29.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. A gap in one wire is bridged by a cotton thread. Does the bulb glow? (a) Yes (b) No
30. 30.🤖 if (light < 300) { lamp ON } else { lamp OFF }
    The light sensor reads 236. What happens? (a) lamp OFF (b) lamp ON
31. 31.🔺 A 1.5 V supply is joined across a 150 Ω resistor. What current flows (in milliamperes, mA)?
32. 32.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 6 hours. How many watt-hours (Wh) are saved?
33. 33.🤖 if (light < 300) { lamp ON } else { lamp OFF }
    The light sensor reads 431. What happens? (a) lamp OFF (b) lamp ON
34. 34.✏️ In a circuit diagram, which part is drawn as a circle with V inside? (a) motor (b) bulb (c) battery (d) voltmeter
35. 35.Which of these is measured in volts (V)? (a) how much a part resists (b) resistance (c) energy used each second (d) voltage
36. 36.🔢 To plan an electronics project, which comes first: “draw the circuit diagram” or “build it with an adult”? (a) draw the circuit diagram (b) build it with an adult
37. 37.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the pins (b) the voltage regulator (c) the reset button (d) the main chip
38. 38.True or false: a wind-up toy usually has a microcontroller inside. (a) True (b) False
39. 39.🔢 To plan an electronics project, what comes right after “pick a problem to solve”? (a) test it and fix it (b) build it with an adult (c) draw the circuit diagram (d) list inputs and outputs
40. 40.🔋 Does a bicycle dynamo give electricity or use electricity? (a) uses electricity (b) gives electricity

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