Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 179 · 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.🔋 4 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)? =
2. 2.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
3. 3.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) bigger (c) zero (d) stay the same
4. 4.🔍 Which is the odd one out? (a) a woollen thread (b) a safety pin (c) a glass marble (d) a rubber eraser
5. 5.🔋 Does a water pump give electricity or use electricity? (a) gives electricity (b) uses electricity
6. 6.🤖 if (temperature > 30) { fan ON } else { fan OFF }
   The temperature sensor reads 24 °C. What happens? (a) fan ON (b) fan OFF
7. 7.⏱️ repeat 7 times { buzzer ON; wait 800 ms; buzzer OFF; wait 1000 ms }
   How many milliseconds does this take in all?
8. 8.🌈 A resistor has the colour bands blue, brown, yellow. What is its value in kilo-ohms (kΩ)? =
9. 9.🤖 if (temperature > 33) { show “Hot” } else if (temperature > 24) { show “Warm” } else { show “Cool” }
   The temperature is 17 °C. What is shown? (a) Warm (b) Cool (c) Hot
10. 10.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an input (c) a power source (d) an output
11. 11.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is ON and C is ON. Does the bulb glow? (a) No (b) Yes
12. 12.🔺 A current of 1 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
13. 13.True or false: “how bright a room is” is an analog signal. (a) True (b) False
14. 14.True or false: the ammeter measures voltage. (a) False (b) True
15. 15.True or false: to dry your hands first is safe. (a) False (b) True
16. 16.🔍 Which is the odd one out? (a) a water heater (b) a loudspeaker (c) a buzzer (d) a school bell
17. 17.⚠️ Who should be with you when you build a circuit? (a) a trusted adult (b) a stranger online (c) a younger child (d) nobody
18. 18.🔐 Is it a good or a risky habit to set a strong password? (a) good habit (b) risky habit
19. 19.Which of these is safe? (a) poke things in a socket (b) throw cells in a fire (c) use mains for a project (d) use small battery cells
20. 20.🔍 Which is the odd one out? (a) an LED (b) a keypad (c) a motion sensor (d) a sound sensor
21. 21.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) the loop is complete (d) a wire is cut
22. 22.Which job needs a light sensor? (a) open blinds at sunrise (b) start a fan when hot (c) warn of a gas leak (d) stop a robot near walls
23. 23.Which of these gives us electricity? (a) a cell (b) a water pump (c) an air conditioner (d) a computer
24. 24.🔘 Which kind of switch stays where you flip it? (a) a push button (b) a tilt switch (c) a reed switch (d) a toggle switch
25. 25.🌈 Which band is read first on a resistor? (a) the gold band (b) any band (c) the one nearest an end (d) the widest gap
26. 26.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 23) { show “Warm” } else { show “Cool” }
    The temperature is 22 °C. What is shown? (a) Cool (b) Warm (c) Hot
27. 27.🔐 Who should decide which smart devices go in a child’s room? (a) an online stranger (b) the app’s adverts (c) a parent or guardian (d) nobody at all
28. 28.Which of these wastes electricity? (a) leave fridge door open (b) use LED lamps (c) unplug idle chargers (d) set the AC to 24 °C
29. 29.Which drawing is the symbol for a cell? (a) one tall, one short bar (b) two or more cell symbols (c) a dot where wires meet (d) triangle, bar and arrows
30. 30.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the process (b) the input (c) the output (d) the battery
31. 31.🔍 Which is the odd one out? (a) a ceiling fan (b) a room heater (c) a mixer grinder (d) an electric drill
32. 32.🌈 A resistor has the colour bands green, brown, black. What is its value (in ohms)?
33. 33.True or false: a washing machine has no microcontroller inside. (a) False (b) True
34. 34.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
35. 35.True or false: a tilt switch stays where you flip it. (a) True (b) False
36. 36.⏱️ loop forever { LED ON; wait 250 ms; LED OFF; wait 200 ms }
    How many milliseconds does one blink (ON + OFF) take?
37. 37.True or false: a circle with an X in it is the symbol for a bulb. (a) True (b) False
38. 38.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
39. 39.🧮 Resistors of 33 Ω, 47 Ω, 20 Ω and 20 Ω are joined in series. What is the total resistance (in ohms)?
40. 40.Which of these is a good habit? (a) share camera links (b) set a strong password (c) share the Wi-Fi key (d) tap unknown app links

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