Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 406 · 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 battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
2. 2.Which drawing is the symbol for a voltmeter? (a) one tall, one short bar (b) triangle against a bar (c) a circle with V inside (d) a line lifted at a gap
3. 3.🧭 Which part of a microcontroller board brings power and code? (a) the main chip (b) the pins (c) the USB port (d) the power LED
4. 4.True or false: a steel spoon is a conductor. (a) False (b) True
5. 5.✏️ In a circuit diagram, which part is drawn as a plain rectangle? (a) resistor (b) motor (c) cell (d) LED
6. 6.True or false: a potentiometer is a resistance knob. (a) False (b) True
7. 7.Which of these is a conductor? (a) a wooden stick (b) a metal paper clip (c) a woollen thread (d) a plastic straw
8. 8.🔺 A current of 20 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
9. 9.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 90 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
10. 10.Which of these means the circuit is closed? (a) the switch is OFF (b) a wire is cut (c) the bulb is unscrewed (d) the switch is ON
11. 11.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
12. 12.🧾 A 250 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
13. 13.⚠️ Is it safe to poke things in a socket? (a) not safe (b) safe
14. 14.⏱️ A program says “wait 2250 ms”. How many seconds is that? =
15. 15.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
16. 16.✏️ In a circuit diagram, which part is drawn as a circle with a cross? (a) resistor (b) cell (c) battery (d) bulb
17. 17.🤖 Which is a safe power source for a beginner microcontroller board? (a) a wall socket directly (b) bare mains wires (c) USB or a 9 V battery (d) a 230 V cable
18. 18.⚡ A 6 W device works on 6 V. What current does it take (in amperes)? =
19. 19.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) by Wi-Fi (c) in parallel (d) not joined
20. 20.🔁 What must there be for a current to flow? (a) a broken path (b) one loose end (c) a complete loop (d) a plastic gap
21. 21.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 11 cm. What happens? (a) buzzer is silent (b) buzzer beeps
22. 22.True or false: on a cell, “usually the black wire” means the − (negative) end. (a) False (b) True
23. 23.⚡ A 3 W device works on 12 V. What current does it take (in amperes)? =
24. 24.🔺 A current of 50 mA flows through a 470 Ω resistor. What is the voltage across it (in volts)? =
25. 25.🔍 Which is the odd one out? (a) keep drinks far away (b) poke things in a socket (c) use mains for a project (d) fly a kite near wires
26. 26.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 volt (c) 1 ampere (d) 1 kilowatt-hour (kWh)
27. 27.What does a tilt switch do? (a) springs back when let go (b) stays where you flip it (c) slides side to side (d) closes when tipped over
28. 28.True or false: on a cell, “the shorter symbol line” means the − (negative) end. (a) False (b) True
29. 29.⚡ What does a school bell mainly change electricity into? (a) sound (b) light (c) movement (d) heat
30. 30.🔐 Is it a good or a risky habit to read app permissions? (a) risky habit (b) good habit
31. 31.True or false: on a cell, “the flat end” means the − (negative) end. (a) True (b) False
32. 32.📶 Digital or analog: how bright a room is? (a) analog (b) digital
33. 33.🔍 Which is the odd one out? (a) use daylight to read (b) unplug idle chargers (c) leave the TV on standby (d) close the fridge quickly
34. 34.What does a toggle switch do? (a) works only while pressed (b) slides side to side (c) closes near a magnet (d) stays where you flip it
35. 35.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) pauses for half a second (c) turns the LED off (d) blinks 500 times
36. 36.💡 2 identical bulbs are joined in series with a 4 V battery (ideal wires). How many volts does each bulb get? =
37. 37.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) a fuse (c) an input (d) an output
38. 38.🧮 Resistors of 10 Ω and 150 Ω are joined in series. What is the total resistance (in ohms)?
39. 39.🧾 A family uses 180 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
40. 40.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) False (b) True

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