Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 757 · 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.🤖 if (light < 300) { lamp ON } else { lamp OFF }
   The light sensor reads 371. What happens? (a) lamp ON (b) lamp OFF
2. 2.True or false: energy used each second is measured in watts (W). (a) False (b) True
3. 3.True or false: “a door: open or shut” is a digital signal. (a) True (b) False
4. 4.🔍 Which sensor would you use to switch on lamps at dusk? (a) a gas sensor (b) a light sensor (c) a temperature sensor (d) a distance sensor
5. 5.🔢 To plan an electronics project, which comes first: “test it and fix it” or “list inputs and outputs”? (a) test it and fix it (b) list inputs and outputs
6. 6.🔍 Which is the odd one out? (a) a wind-up clock (b) a fitness band with app (c) an app-controlled bulb (d) a Wi-Fi doorbell camera
7. 7.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a rubber band. Does the bulb glow? (a) No (b) Yes
8. 8.True or false: energy used each second is measured in ohms (Ω). (a) False (b) True
9. 9.🔺 A current of 1 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
10. 10.Which of these is safe? (a) build with an adult near (b) climb an electric pole (c) open a phone charger (d) use mains for a project
11. 11.🧮 Two resistors in parallel give a total that is … (a) their sum (b) less than either one (c) always zero (d) more than either one
12. 12.🔢 To plan an electronics project, what comes right after “build it with an adult”? (a) pick a problem to solve (b) list inputs and outputs (c) test it and fix it (d) draw the circuit diagram
13. 13.🌈 A resistor has the colour bands grey, yellow, orange. What is its value in kilo-ohms (kΩ)? =
14. 14.🔁 x = 3
    repeat 5 times { x = x × 2 }
    What is x at the end?
15. 15.🔐 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) share it with friends (d) ask a parent first
16. 16.True or false: to run fans in empty rooms saves electricity. (a) True (b) False
17. 17.🔗 Series or parallel circuit: “used in house wiring”? (a) parallel (b) series
18. 18.True or false: “how bright a room is” is a digital signal. (a) True (b) False
19. 19.⚠️ About how many volts do home sockets in India supply? (a) 12 V (b) 9 V (c) 230 V (d) 1.5 V
20. 20.True or false: on an LED, the round-side leg is the anode (+). (a) False (b) True
21. 21.🔺 A current of 2 A flows when 30 V is joined across a resistor. What is its resistance (in ohms)?
22. 22.🧩 Which part changes electrical energy into movement? (a) an LED (b) a resistor (c) a motor (d) a fuse
23. 23.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 300 ms }
    How many milliseconds does one blink (ON + OFF) take?
24. 24.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 4 glow? (a) Yes (b) No
25. 25.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
26. 26.⚡ 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
27. 27.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the output (b) the input (c) the battery (d) the process
28. 28.True or false: a doorbell mainly makes sound. (a) False (b) True
29. 29.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
30. 30.🤖 Microcontroller or laptop: which one uses very little power? (a) microcontroller (b) laptop
31. 31.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) bulb (b) battery (c) resistor (d) LED
32. 32.Which drawing is the symbol for a battery? (a) a plain rectangle (b) a line lifted at a gap (c) two or more cell symbols (d) a circle with A inside
33. 33.True or false: to use mains for a project is not safe. (a) False (b) True
34. 34.⚡ A device works on 24 V and takes 3 A. What is its power (in watts)? =
35. 35.Which of these uses electricity? (a) a television (b) a cell (c) a generator (d) a bicycle dynamo
36. 36.What does a motor do? (a) glows using little power (b) stores a little charge (c) makes things spin (d) senses how bright it is
37. 37.🔐 Why install updates on IoT devices? (a) they make it heavier (b) they fix security holes (c) they change the colour (d) they delete the Wi-Fi
38. 38.🤖 if (temperature > 35) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
    The temperature is 35 °C. What is shown? (a) Warm (b) Cool (c) Hot
39. 39.🔍 Which is the odd one out? (a) a speaker (b) a buzzer (c) a temperature sensor (d) a motor
40. 40.🔍 Which is the odd one out? (a) dry your hands first (b) touch a fallen wire (c) use small battery cells (d) take cells out after use

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