Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 102 · 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 job needs a light sensor? (a) spot someone walking in (b) water a dry plant (c) switch on lamps at dusk (d) switch on with a clap
2. 2.🔁 x = 3
   repeat 4 times { x = x × 2 }
   What is x at the end?
3. 3.🗺️ In an input → process → output plan, is “an alert on the phone” the input, the process or the output? (a) process (b) output (c) input
4. 4.🔍 Which is the odd one out? (a) a steel coin (b) a plastic ruler (c) a paper strip (d) a dry cork
5. 5.🌐 In an IoT system, which part stores data online? (a) phone app (b) cloud server (c) sensor (d) actuator
6. 6.🤖 if (temperature > 38) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
   The temperature is 13 °C. What is shown? (a) Warm (b) Cool (c) Hot
7. 7.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) post it online (b) type it all in (c) ask a parent first (d) share it with friends
8. 8.🌈 A resistor has the colour bands red, brown, brown. What is its value (in ohms)?
9. 9.🤖 “if (A AND B)” is true when … (a) both A and B are true (b) both are false (c) only A is true (d) only B is true
10. 10.What does a potentiometer do? (a) glows using little power (b) is a resistance knob (c) smooths a wobbly supply (d) stores a little charge
11. 11.⚡ A 36 W device works on 24 V. What current does it take (in amperes)? =
12. 12.⚠️ Someone is getting a shock and is still touching a wire. What should you do? (a) pour water on them (b) wait and watch (c) pull them by the hand (d) shout for an adult
13. 13.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 24) { show “Warm” } else { show “Cool” }
    The temperature is 23 °C. What is shown? (a) Warm (b) Hot (c) Cool
14. 14.✏️ In a circuit diagram, wires are usually drawn as … (a) wavy lines (b) dotted circles (c) straight lines (d) little stars
15. 15.True or false: to set up with a parent is a good habit. (a) False (b) True
16. 16.⚡ A cell changes stored chemical energy into which kind of energy? (a) wind energy (b) sound energy (c) electrical energy (d) nuclear energy
17. 17.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) none (c) two (d) one
18. 18.True or false: a digital thermometer usually has a microcontroller inside. (a) True (b) False
19. 19.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 100 (b) 1024 (c) 1000 (d) 10
20. 20.🌈 A resistor has the colour bands white, green, orange. What is its value (in ohms)?
21. 21.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) an open circuit (b) a short circuit (c) a safe circuit (d) a parallel circuit
22. 22.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
23. 23.Which of these gives us electricity? (a) a mobile phone (b) a television (c) a solar panel (d) a refrigerator
24. 24.🗺️ In an input → process → output plan, is “a soil moisture reading” the input, the process or the output? (a) process (b) input (c) output
25. 25.🔍 Which is the odd one out? (a) a dry cork (b) a rubber eraser (c) an iron nail (d) a cotton thread
26. 26.💡 3 identical bulbs are joined in series with a 4.5 V battery (ideal wires). How many volts does each bulb get? =
27. 27.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) only when both are ON (b) never (c) when either is ON (d) only when both are OFF
28. 28.🔺 A current of 50 mA flows when 16.5 V is joined across a resistor. What is its resistance (in ohms)?
29. 29.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a dry cork. Does the bulb glow? (a) Yes (b) No
30. 30.True or false: two equal parallel lines is the symbol for a capacitor. (a) True (b) False
31. 31.🔁 repeat 4 times { repeat 3 times { beep } }
    How many beeps are there?
32. 32.💡 5 identical bulbs are joined in series with a 15 V battery (ideal wires). How many volts does each bulb get? =
33. 33.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
34. 34.Which of these is not safe? (a) build with an adult near (b) dry your hands first (c) stop if a part gets hot (d) touch a fallen wire
35. 35.Which job is done by the pins? (a) runs the program (b) restarts the program (c) shows the board is on (d) connect sensors and LEDs
36. 36.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 ampere (c) 1 volt (d) 1 kilowatt-hour (kWh)
37. 37.Which of these has no microcontroller inside? (a) a smart watch (b) a digital thermometer (c) a washing machine (d) a spinning top
38. 38.🔋 Does a cell give electricity or use electricity? (a) uses electricity (b) gives electricity
39. 39.🔍 A distance sensor sends a sound pulse and hears the echo 10 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
40. 40.✏️ In a circuit diagram, which part is drawn as triangle, bar and arrows? (a) LED (b) switch (c) ammeter (d) cell

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