Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 239 · 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.🌐 What does IoT stand for? (a) Inside of Toys (b) Input of Tools (c) Internet of Things (d) Internet of Talk
2. 2.🔍 Which is the odd one out? (a) a safety pin (b) a metal paper clip (c) a glass marble (d) a copper wire
3. 3.⚡ A device works on 3 V and takes 0.5 A. What is its power (in watts)? =
4. 4.🌈 A resistor has the colour bands brown, blue, red. What is its value in kilo-ohms (kΩ)? =
5. 5.True or false: “a temperature reading” is the input. (a) False (b) True
6. 6.🌈 A resistor has the colour bands red, violet, orange. What is its value (in ohms)?
7. 7.Which of these is a good habit? (a) ignore update messages (b) share only needed data (c) tap unknown app links (d) accept every permission
8. 8.🔺 In the V-I-R triangle, how do we find V? (a) V = I ÷ R (b) V = R ÷ I (c) V = I × R (d) V = I + R
9. 9.What does a tilt switch do? (a) works only while pressed (b) closes when tipped over (c) stays where you flip it (d) closes near a magnet
10. 10.🧭 Which part of a microcontroller board restarts the program? (a) the pins (b) the voltage regulator (c) the power LED (d) the reset button
11. 11.🧩 Which component lets current go one way? (a) LDR (b) motor (c) LED (d) diode
12. 12.Which drawing is the symbol for an LED? (a) a circle with A inside (b) triangle, bar and arrows (c) a long and a short line (d) two or more cell symbols
13. 13.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
14. 14.🔍 Which is the odd one out? (a) leave fridge door open (b) set the AC to 24 °C (c) close the fridge quickly (d) use daylight to read
15. 15.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) smaller (c) bigger (d) stay the same
16. 16.🔍 Which is the odd one out? (a) an electric kettle (b) a mixer grinder (c) a rice cooker (d) an electric iron
17. 17.True or false: a school bell mainly gives out light. (a) False (b) True
18. 18.Which of these is a conductor? (a) a plastic straw (b) aluminium foil (c) a woollen thread (d) a dry cork
19. 19.Which job is done by the power LED? (a) runs the program (b) restarts the program (c) shows the board is on (d) connect sensors and LEDs
20. 20.True or false: a dot where wires meet is the symbol for a junction. (a) False (b) True
21. 21.True or false: “the pump turns on” is the input. (a) True (b) False
22. 22.True or false: two equal parallel lines is the symbol for a switch. (a) False (b) True
23. 23.📏 How many ohms (Ω) is 6.4 kΩ?
24. 24.🔺 A current of 1 A flows when 10 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 1 hour?
26. 26.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 540 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
27. 27.🔁 What do we call a circuit with a break in it? (a) an open circuit (b) a full circuit (c) a series circuit (d) a closed circuit
28. 28.True or false: a candle usually has a microcontroller inside. (a) False (b) True
29. 29.True or false: an iron nail is a conductor. (a) False (b) True
30. 30.📏 How many milliamperes (mA) is 1.87 A?
31. 31.Which of these is the input? (a) decide if soil is dry (b) the fan starts (c) a button press (d) an LED lights up
32. 32.🔋 4 identical 1.5 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
33. 33.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 watt (c) 1 volt (d) 1 ampere
34. 34.🌐 Each reading a sensor sends is 50 bytes. How many bytes do 200 readings take?
35. 35.💡 Why is house wiring done in parallel? (a) to make bulbs dim (b) to save copper only (c) so all go off together (d) each gets full voltage
36. 36.📶 A pin set LOW gives about … (a) 9 V (b) 5 V (c) 1.5 V (d) 0 V
37. 37.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 1 hour. How many watt-hours (Wh) are saved?
38. 38.🔌 Is a dry cork a conductor or an insulator? (a) a conductor (b) an insulator
39. 39.True or false: a candle has no microcontroller inside. (a) True (b) False
40. 40.Which of these is not safe? (a) dry your hands first (b) use small battery cells (c) throw cells in a fire (d) keep drinks far away

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