Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 22 · 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: to keep an incubator warm, use a motion sensor. (a) True (b) False
2. 2.Which of these is an input? (a) a light sensor (b) an LED (c) a speaker (d) a small display
3. 3.🔍 Which is the odd one out? (a) an alert on the phone (b) decide if soil is dry (c) count button presses (d) check if temp > 30
4. 4.True or false: “each gets the full volts” is true of a parallel circuit. (a) True (b) False
5. 5.🔍 Which is the odd one out? (a) decide if soil is dry (b) check if temp > 30 (c) compare with a limit (d) a temperature reading
6. 6.True or false: a push button slides side to side. (a) True (b) False
7. 7.Which of these wastes electricity? (a) set the AC to 24 °C (b) switch off empty rooms (c) run fans in empty rooms (d) close the fridge quickly
8. 8.🧮 Resistors of 20 Ω, 150 Ω, 50 Ω and 470 Ω are joined in series. What is the total resistance (in ohms)?
9. 9.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 530 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
10. 10.⚡ A cell changes stored chemical energy into which kind of energy? (a) wind energy (b) nuclear energy (c) sound energy (d) electrical energy
11. 11.🔺 A current of 1 A flows when 6 V is joined across a resistor. What is its resistance (in ohms)?
12. 12.⏱️ A program says “wait 1750 ms”. How many seconds is that? =
13. 13.🤖 “if (A AND B)” is true when … (a) only A is true (b) both A and B are true (c) both are false (d) only B is true
14. 14.🧮 A 0.9 V battery is joined to 6 Ω and 3 Ω resistors in series. What current flows (in amperes)? =
15. 15.🔐 Which is the strongest password for a home smart camera? (a) 123456 (b) password (c) Tiger#Lamp42!Moon (d) admin
16. 16.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 370 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
17. 17.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) series (b) parallel
18. 18.Which of these is true of a series circuit? (a) one out, the rest glow (b) many paths for current (c) own switch for each bulb (d) one bulb out, all go out
19. 19.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = V + R (c) I = R ÷ V (d) I = V × R
20. 20.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 780 Ω resistor? (a) violet-grey-brown (b) grey-violet-brown (c) violet-grey-black (d) violet-grey-red
21. 21.🔘 A cell, a bulb and switches A, B, C and D are joined one after another in a single loop (series). A is OFF, B is OFF, C is OFF and D is ON. Does the bulb glow? (a) No (b) Yes
22. 22.⚠️ What protects home wiring by melting or tripping when too much current flows? (a) a long wire (b) a fuse or MCB (c) a plug top (d) a bulb
23. 23.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
24. 24.True or false: to make a parking alarm, use a distance sensor. (a) True (b) False
25. 25.🔍 Which sensor would you use to stop a robot near walls? (a) a rain sensor (b) a sound sensor (c) a distance sensor (d) a temperature sensor
26. 26.🔢 To run one loop of a plant-watering program, which comes first: “read the soil sensor” or “switch the pump on/off”? (a) switch the pump on/off (b) read the soil sensor
27. 27.⚙️ What is an actuator? (a) a sensor (b) an output that acts (c) a program (d) a battery
28. 28.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 580 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
29. 29.🔌 Which part of a screwdriver should an electrician hold? (a) the steel shaft (b) the plastic handle (c) the metal tip (d) the bare end
30. 30.🔁 What do we call a circuit with a break in it? (a) an open circuit (b) a closed circuit (c) a full circuit (d) a series circuit
31. 31.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?
32. 32.🌈 A gold fourth band on a resistor means the value may be off by … (a) 50 % (b) 5 % (c) 0 % (d) 25 %
33. 33.🔁 count = 0
    repeat 9 times { count = count + 5 }
    What is count at the end?
34. 34.True or false: a microcontroller runs one small program. (a) False (b) True
35. 35.🔗 Series or parallel circuit: “own switch for each bulb”? (a) parallel (b) series
36. 36.🔺 A 0.8 V supply is joined across a 4 Ω resistor. What current flows (in amperes)? =
37. 37.🧩 A capacitor in a circuit can … (a) measure heat (b) make light (c) spin a wheel (d) store charge briefly
38. 38.💡 4 identical bulbs are in parallel and each bulb has its own switch on its path. 2 of the switches are OFF and the rest are ON. How many bulbs glow?
39. 39.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
40. 40.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 80 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF

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