Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 343 · 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 drawing is the symbol for a motor? (a) a small empty box (b) a circle with a cross (c) a circle with M inside (d) two equal parallel lines
2. 2.Which of these mainly makes movement? (a) a ceiling fan (b) a night lamp (c) a toaster (d) a tube light
3. 3.Which job is done by the main chip? (a) connect sensors and LEDs (b) runs the program (c) restarts the program (d) shows the board is on
4. 4.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
5. 5.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 5 V supply. What current flows (in mA)?
6. 6.⚠️ Is it safe to build with an adult near? (a) not safe (b) safe
7. 7.🤖 Where does the board keep its program when the power is off? (a) the power LED (b) flash memory (c) the USB cable (d) the resistor
8. 8.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an input (c) a power source (d) an output
9. 9.True or false: “how loud a sound is” is an analog signal. (a) True (b) False
10. 10.True or false: to throw cells in a fire is not safe. (a) True (b) False
11. 11.⚡ A device works on 24 V and takes 2 A. What is its power (in watts)? =
12. 12.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a graphite rod across the gap. Does the bulb glow? (a) No (b) Yes
13. 13.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 96000 Ω resistor? (a) white-blue-red (b) blue-white-orange (c) white-blue-yellow (d) white-blue-orange
14. 14.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
15. 15.🌈 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
16. 16.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark an 82 Ω resistor? (a) red-grey-black (b) grey-red-brown (c) white-red-black (d) grey-red-black
17. 17.True or false: to leave the TV on standby saves electricity. (a) False (b) True
18. 18.🔺 A current of 0.5 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🔁 repeat 5 times { repeat 5 times { beep } }
    How many beeps are there?
20. 20.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
21. 21.🔺 A 1 V supply is joined across a 100 Ω resistor. What current flows (in milliamperes, mA)?
22. 22.What does the phone app do? (a) shows data to you (b) acts on a command (c) stores data online (d) carries the data
23. 23.💡 Why is house wiring done in parallel? (a) to save copper only (b) so all go off together (c) each gets full voltage (d) to make bulbs dim
24. 24.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a light sensor (c) a soil moisture sensor (d) a temperature sensor
25. 25.🔁 count = 0
    while (count < 8) { count = count + 2 }
    How many times does the loop run?
26. 26.🔺 In the V-I-R triangle, how do we find R? (a) R = V + I (b) R = V × I (c) R = V ÷ I (d) R = I ÷ V
27. 27.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) both parts (c) the if part (d) the else part
28. 28.📶 Digital or analog: the room temperature? (a) analog (b) digital
29. 29.🔺 A 7.5 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
30. 30.⚡ Power tells us … (a) the size of a cell (b) energy used each second (c) the colour of light (d) the length of a wire
31. 31.True or false: “a break stops every bulb” is true of a series circuit. (a) True (b) False
32. 32.🔍 Which is the odd one out? (a) share camera links (b) keep factory passwords (c) post your live location (d) cover unused cameras
33. 33.🔍 Which is the odd one out? (a) the fan starts (b) an LED lights up (c) count button presses (d) the pump turns on
34. 34.💡 4 identical bulbs are in parallel and each one takes 0.1 A. What total current (in amperes) comes from the battery? =
35. 35.Which drawing is the symbol for a voltmeter? (a) a dot where wires meet (b) triangle, bar and arrows (c) a circle with V inside (d) one tall, one short bar
36. 36.🔘 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 OFF, B is ON and C is ON. Does the bulb glow? (a) No (b) Yes
37. 37.🔐 Is it a good or a risky habit to cover unused cameras? (a) risky habit (b) good habit
38. 38.🔋 Cells joined + to − in a row (series) give … (a) the same voltage (b) a bigger voltage (c) a smaller voltage (d) no voltage
39. 39.🔍 Which is the odd one out? (a) touch a switch when wet (b) climb an electric pole (c) stop if a part gets hot (d) use mains for a project
40. 40.💡 2 identical bulbs are in parallel and each one takes 0.1 A. What total current (in amperes) comes from the battery? =

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