Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 512 · 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 0.6 W device works on 6 V. What current does it take (in amperes)? =
2. 2.True or false: power is measured in watts (W). (a) False (b) True
3. 3.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) straight lines (c) wavy lines (d) dotted circles
4. 4.🧭 Which part of a microcontroller board shows the board is on? (a) the pins (b) the power LED (c) the reset button (d) the main chip
5. 5.True or false: to share only needed data is a good habit. (a) False (b) True
6. 6.⚡ A device works on 6 V and takes 1 A. What is its power (in watts)? =
7. 7.🔢 To plan an electronics project, which is the LAST step? (a) build it with an adult (b) test it and fix it (c) pick a problem to solve (d) list inputs and outputs
8. 8.Which of these means the circuit is closed? (a) a cell is taken out (b) the loop is complete (c) a wire is cut (d) the switch is OFF
9. 9.🔺 A current of 20 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
10. 10.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
11. 11.🔍 Which sensor would you use to open blinds at sunrise? (a) a rain sensor (b) a light sensor (c) a gas sensor (d) a soil moisture sensor
12. 12.🌈 In the resistor colour code, which number does red stand for?
13. 13.🔺 A current of 10 mA flows through a 400 Ω resistor. What is the voltage across it (in volts)? =
14. 14.🔘 Which kind of switch flips up or down? (a) a toggle switch (b) a slide switch (c) a reed switch (d) a push button
15. 15.True or false: to cover unused cameras is a good habit. (a) True (b) False
16. 16.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) waits 500 seconds (c) pauses for half a second (d) turns the LED off
17. 17.True or false: a plastic straw is an insulator. (a) True (b) False
18. 18.🔢 To run one loop of a plant-watering program, which comes first: “wait a few seconds” or “compare with the limit”? (a) compare with the limit (b) wait a few seconds
19. 19.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 330 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
20. 20.True or false: a plastic ruler is an insulator. (a) True (b) False
21. 21.🧮 A 2 V battery is joined to 2 Ω and 8 Ω resistors in series. What current flows (in amperes)? =
22. 22.⚠️ About how many volts do home sockets in India supply? (a) 230 V (b) 9 V (c) 1.5 V (d) 12 V
23. 23.🔍 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
24. 24.🌐 A weather station sends one reading every 10 seconds. How many readings does it send in 1 minute?
25. 25.🔋 What should you do with used-up cells? (a) throw them in a fire (b) cut them open (c) bury them in soil (d) give them for recycling
26. 26.Which job needs a distance sensor? (a) spot someone walking in (b) measure classroom noise (c) stop a robot near walls (d) switch on with a clap
27. 27.True or false: on an LED, the longer leg is the cathode (−). (a) True (b) False
28. 28.What does a tilt switch do? (a) works only while pressed (b) closes when tipped over (c) closes near a magnet (d) stays where you flip it
29. 29.🌈 A resistor has the colour bands brown, blue, yellow. What is its value in kilo-ohms (kΩ)? =
30. 30.🔢 To run one loop of a plant-watering program, which comes first: “read the soil sensor” or “wait a few seconds”? (a) wait a few seconds (b) read the soil sensor
31. 31.🧩 Which part changes electrical energy into movement? (a) a fuse (b) a motor (c) an LED (d) a resistor
32. 32.🧮 A 68 Ω resistor is joined in series with two equal 200 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
33. 33.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
34. 34.🔺 A 6 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
35. 35.🔋 5 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
36. 36.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) by Wi-Fi (c) in parallel (d) in series
37. 37.🔍 Which sensor would you use to make a parking alarm? (a) a temperature sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
38. 38.True or false: a plain rectangle is the symbol for a battery. (a) True (b) False
39. 39.🌈 A resistor has the colour bands orange, blue, black. What is its value (in ohms)?
40. 40.📏 In the water-pipe picture of a circuit, voltage is like … (a) the tap handle (b) the water pressure (c) the pipe colour (d) the water tank lid

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