Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 967 · 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.🔺 In the V-I-R triangle, how do we find V? (a) V = I ÷ R (b) V = I × R (c) V = R ÷ I (d) V = I + R
2. 2.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 2.75 V supply. What current flows (in mA)?
3. 3.⚡ What does a buzzer mainly change electricity into? (a) movement (b) heat (c) sound (d) light
4. 4.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = I ÷ V (d) P = V + I
5. 5.Which job is done by the USB port? (a) runs the program (b) restarts the program (c) brings power and code (d) connect sensors and LEDs
6. 6.🔁 What must there be for a current to flow? (a) a plastic gap (b) one loose end (c) a broken path (d) a complete loop
7. 7.🧮 Two equal 220 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
8. 8.💡 5 identical bulbs are joined in series with a 15 V battery (ideal wires). How many volts does each bulb get? =
9. 9.Which drawing is the symbol for a junction? (a) a circle with V inside (b) a dot where wires meet (c) a circle with an X in it (d) a straight line
10. 10.⚡ A 2.25 W device works on 9 V. What current does it take (in amperes)? =
11. 11.🔘 A bulb and a cell are joined through 6 switches on 6 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
12. 12.True or false: a resistor stores a little charge. (a) False (b) True
13. 13.True or false: a microcontroller runs one small program. (a) False (b) True
14. 14.🔌 Which part of a screwdriver should an electrician hold? (a) the metal tip (b) the plastic handle (c) the steel shaft (d) the bare end
15. 15.Which of these is the output? (a) count button presses (b) a button press (c) a buzzer beeps (d) compare with a limit
16. 16.🔍 Which is the odd one out? (a) a copper wire (b) a woollen thread (c) an iron nail (d) a safety pin
17. 17.True or false: a rice cooker mainly gives out light. (a) True (b) False
18. 18.🧮 Three equal 60 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
19. 19.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = R ÷ V (c) I = V × R (d) I = V + R
20. 20.🔁 repeat 5 times { repeat 2 times { beep } }
    How many beeps are there?
21. 21.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 6800 Ω resistor? (a) blue-grey-red (b) blue-grey-orange (c) blue-grey-brown (d) grey-blue-red
22. 22.📶 How many states can a digital pin have? (a) a thousand (b) one (c) ten (d) two
23. 23.What does the microcontroller do? (a) acts on a command (b) reads values, decides (c) carries the data (d) shows data to you
24. 24.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
25. 25.True or false: to touch a fallen wire is safe. (a) False (b) True
26. 26.⏱️ repeat 4 times { buzzer ON; wait 200 ms; buzzer OFF; wait 400 ms }
    How many milliseconds does this take in all?
27. 27.Which of these is safe? (a) use a cable with cuts (b) use mains for a project (c) fly a kite near wires (d) keep drinks far away
28. 28.True or false: to fly kites in open fields is not safe. (a) False (b) True
29. 29.🤖 if (light < 400) { lamp ON } else { lamp OFF }
    The light sensor reads 343. What happens? (a) lamp OFF (b) lamp ON
30. 30.🤖 What is a microcontroller? (a) a kind of bulb (b) a computer on one chip (c) a big desktop computer (d) a type of battery
31. 31.Which of these mainly makes sound? (a) an electric toy car (b) a rice cooker (c) a doorbell (d) a water heater
32. 32.🗺️ Before building a project, what should you write down first? (a) the box colour (b) nothing at all (c) the final price (d) inputs and outputs
33. 33.🔁 count = 1
    while (count < 13) { count = count + 4 }
    How many times does the loop run?
34. 34.Which of these is not safe? (a) fly kites in open fields (b) use small battery cells (c) take cells out after use (d) poke things in a socket
35. 35.🧩 Which component smooths a wobbly supply? (a) fuse (b) capacitor (c) potentiometer (d) resistor
36. 36.True or false: to build with an adult near is not safe. (a) False (b) True
37. 37.🔁 What does a variable do in a program? (a) blinks an LED (b) stores a value (c) joins two wires (d) measures light
38. 38.True or false: a circle with an X in it is the symbol for a bulb. (a) False (b) True
39. 39.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
40. 40.🔢 To plan an electronics project, what comes right after “build it with an adult”? (a) test it and fix it (b) pick a problem to solve (c) draw the circuit diagram (d) list inputs and outputs

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