Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 993 · 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 job is done by the main chip? (a) keeps the voltage steady (b) connect sensors and LEDs (c) brings power and code (d) runs the program
2. 2.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) capacitor (b) wire (c) cell (d) battery
3. 3.⚠️ What protects home wiring by melting or tripping when too much current flows? (a) a long wire (b) a bulb (c) a fuse or MCB (d) a plug top
4. 4.💡 3 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 2 glow? (a) No (b) Yes
5. 5.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a plastic straw across the gap. Does the bulb glow? (a) No (b) Yes
6. 6.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 2 hours?
7. 7.⚡ A device works on 24 V and takes 2 A. What is its power (in watts)? =
8. 8.🔦 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 plastic ruler. Does the bulb glow? (a) No (b) Yes
9. 9.⚡ A 36 W device works on 24 V. What current does it take (in amperes)? =
10. 10.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
11. 11.🔘 Which kind of switch stays where you flip it? (a) a reed switch (b) a toggle switch (c) a tilt switch (d) a push button
12. 12.True or false: a TV remote has no microcontroller inside. (a) False (b) True
13. 13.True or false: “one bulb out, all go out” is true of a series circuit. (a) True (b) False
14. 14.True or false: a ceiling fan mainly makes movement. (a) False (b) True
15. 15.🔍 Which is the odd one out? (a) leave the TV on standby (b) unplug idle chargers (c) iron one shirt at a time (d) run fans in empty rooms
16. 16.⚠️ About how many volts do home sockets in India supply? (a) 12 V (b) 1.5 V (c) 9 V (d) 230 V
17. 17.🌈 A resistor has the colour bands yellow, grey, orange. What is its value (in ohms)?
18. 18.💡 Why does an LED need a resistor in series? (a) to make it brighter (b) to limit the current (c) to store charge (d) to change its colour
19. 19.Which of these is measured in volts (V)? (a) how much a part resists (b) current (c) voltage (d) resistance
20. 20.True or false: triangle against a bar is the symbol for a bulb. (a) True (b) False
21. 21.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 3.5 V supply. What current flows (in mA)?
22. 22.🗺️ In an input → process → output plan, is “a soil moisture reading” the input, the process or the output? (a) input (b) output (c) process
23. 23.🧩 Which component smooths a wobbly supply? (a) transistor (b) thermistor (c) capacitor (d) fuse
24. 24.🔋 Does a computer give electricity or use electricity? (a) uses electricity (b) gives electricity
25. 25.🤖 if (moisture < 30) { pump ON } else { pump OFF }
    The soil moisture sensor reads 42 %. What happens? (a) pump ON (b) pump OFF
26. 26.🔘 When a switch is ON, the circuit is … (a) open (b) broken (c) cut (d) closed
27. 27.🔍 Which is the odd one out? (a) set a strong password (b) reuse one password (c) keep factory passwords (d) share camera links
28. 28.Which drawing is the symbol for a diode? (a) triangle against a bar (b) a circle with V inside (c) one tall, one short bar (d) a dot where wires meet
29. 29.🔺 A current of 0.25 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
30. 30.🔘 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 ON, B is OFF and C is ON. Does the bulb glow? (a) No (b) Yes
31. 31.🔌 Is a temperature sensor an input or an output for a microcontroller? (a) output (b) input
32. 32.🧮 Three equal 15 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
33. 33.🔌 Is a plastic ruler a conductor or an insulator? (a) an insulator (b) a conductor
34. 34.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = I ÷ V (c) P = V + I (d) P = V × I
35. 35.🌐 In an IoT system, which part reads values, decides? (a) actuator (b) microcontroller (c) sensor (d) phone app
36. 36.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
37. 37.True or false: a resistor blows if current is high. (a) True (b) False
38. 38.🔌 Is a turning knob an input or an output for a microcontroller? (a) output (b) input
39. 39.🔺 A 6 V supply is joined across a 120 Ω resistor. What current flows (in milliamperes, mA)?
40. 40.💡 An LED is joined to a 9 V battery through a 220 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) may burn out (c) lights up

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