Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 691 · 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.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) False (b) True
2. 2.🔺 A current of 0.2 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
3. 3.🔁 x = 4
   repeat 4 times { x = x × 2 }
   What is x at the end?
4. 4.Which job needs a rain sensor? (a) close a window in rain (b) measure classroom noise (c) make a parking alarm (d) switch on lamps at dusk
5. 5.True or false: to tap unknown app links is a risky habit. (a) False (b) True
6. 6.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
7. 7.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 watt (c) 1 volt (d) 1 ampere
8. 8.📶 A pin that reads a push button is set as … (a) an output (b) an input (c) a battery (d) a resistor
9. 9.⚠️ What protects home wiring by melting or tripping when too much current flows? (a) a fuse or MCB (b) a plug top (c) a long wire (d) a bulb
10. 10.True or false: a ceiling fan mainly makes movement. (a) False (b) True
11. 11.🔦 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 aluminium foil. Does the bulb glow? (a) Yes (b) No
12. 12.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False
13. 13.True or false: a laptop has a built-in keyboard. (a) True (b) False
14. 14.Which of these is an input? (a) a small display (b) a sound sensor (c) a speaker (d) an LED
15. 15.🔗 Series or parallel circuit: “a single current path”? (a) series (b) parallel
16. 16.🔦 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 glass marble. Does the bulb glow? (a) Yes (b) No
17. 17.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 220 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
18. 18.🔺 A current of 2 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🔍 Which is the odd one out? (a) take cells out after use (b) fly kites in open fields (c) stop if a part gets hot (d) climb an electric pole
20. 20.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I ÷ R (c) V = I × R (d) V = R ÷ I
21. 21.⚠️ Is it safe to use small battery cells? (a) safe (b) not safe
22. 22.🔺 A 0.6 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
23. 23.What does a diode do? (a) senses how bright it is (b) senses how hot it is (c) lets current go one way (d) beeps for an alarm
24. 24.⚙️ Which actuator would you use to move water to plants? (a) a motor (b) a servo motor (c) a pump (d) an LED
25. 25.📶 How many states can a digital pin have? (a) a thousand (b) ten (c) two (d) one
26. 26.🔍 Which is the odd one out? (a) keep drinks far away (b) take cells out after use (c) throw cells in a fire (d) fly kites in open fields
27. 27.🔢 To get a sensor reading onto a phone, which is the LAST step? (a) the sensor measures (b) it is sent by Wi-Fi (c) the board reads it (d) the app shows it
28. 28.🧩 Which component boosts a small signal? (a) LED (b) motor (c) resistor (d) transistor
29. 29.🧮 Three equal 60 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
30. 30.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) input (b) output (c) process
31. 31.✏️ In a circuit diagram, which part is drawn as one tall, one short bar? (a) motor (b) cell (c) switch (d) voltmeter
32. 32.True or false: a long and a short line is the symbol for a cell. (a) True (b) False
33. 33.Which of these is true of a series circuit? (a) own switch for each bulb (b) one bulb out, all go out (c) many paths for current (d) used in house wiring
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.🤖 if (light < 400) { lamp ON } else { lamp OFF }
    The light sensor reads 316. What happens? (a) lamp ON (b) lamp OFF
36. 36.True or false: a tilt switch stays where you flip it. (a) True (b) False
37. 37.🤖 Microcontroller or laptop: which one has a built-in keyboard? (a) laptop (b) microcontroller
38. 38.🌈 Which band is read first on a resistor? (a) the widest gap (b) the gold band (c) any band (d) the one nearest an end
39. 39.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the glass (c) the switch (d) the base
40. 40.True or false: “a light level reading” is the input. (a) False (b) True

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