Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 309 · 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.🧮 Two equal 10 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
2. 2.🌐 Is a Wi-Fi smart plug an IoT device? (a) an IoT device (b) not an IoT device
3. 3.🌈 A resistor has the colour bands white, grey, red. What is its value in kilo-ohms (kΩ)? =
4. 4.Which of these is measured in amperes (A)? (a) voltage (b) energy used each second (c) current (d) the push of a cell
5. 5.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 640 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
6. 6.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 1024 (b) 100 (c) 1000 (d) 10
7. 7.💡 6 identical bulbs are in parallel and each one takes 0.25 A. What total current (in amperes) comes from the battery? =
8. 8.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) only when both are OFF (b) only when both are ON (c) when either is ON (d) never
9. 9.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) smaller (c) stay the same (d) bigger
10. 10.⚡ A device works on 3 V and takes 0.2 A. What is its power (in watts)? =
11. 11.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put aluminium foil across the gap. Does the bulb glow? (a) No (b) Yes
12. 12.Which of these mainly makes movement? (a) a rice cooker (b) a toaster (c) a street light (d) a ceiling fan
13. 13.🧮 A 0.8 V battery is joined to 5 Ω and 3 Ω resistors in series. What current flows (in amperes)? =
14. 14.🔺 A current of 1.5 A flows when 6 V is joined across a resistor. What is its resistance (in ohms)?
15. 15.🔘 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 ON, B is ON and C is ON. Does the bulb glow? (a) Yes (b) No
16. 16.🔘 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 OFF. Does the bulb glow? (a) Yes (b) No
17. 17.What does a fuse do? (a) boosts a small signal (b) has coloured bands (c) blows if current is high (d) stores a little charge
18. 18.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) in series (c) by Wi-Fi (d) in parallel
19. 19.🔌 Is a graphite rod a conductor or an insulator? (a) an insulator (b) a conductor
20. 20.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 100 (c) 10 (d) 1000
21. 21.🔍 Which is the odd one out? (a) a table fan (b) a school bell (c) a ceiling fan (d) an exhaust fan
22. 22.⚡ A home appliance on the 230 V mains takes 8 A. What is its power (in watts)?
23. 23.🌈 A resistor has the colour bands brown, grey, yellow. What is its value in kilo-ohms (kΩ)? =
24. 24.💡 2 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. How many bulbs glow?
25. 25.Which of these usually has a microcontroller inside? (a) a smart watch (b) a hand pump (c) a plain wall switch (d) a bicycle bell
26. 26.🧮 Five equal 25 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
27. 27.💡 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
28. 28.Which of these is a conductor? (a) a plastic straw (b) a cotton thread (c) a woollen thread (d) a graphite rod
29. 29.🧩 A capacitor in a circuit can … (a) store charge briefly (b) make light (c) spin a wheel (d) measure heat
30. 30.🌈 A resistor has the colour bands violet, brown, brown. What is its value (in ohms)?
31. 31.🔐 Privacy for a smart device means controlling … (a) its battery size (b) who can see your data (c) its colour (d) how loud it beeps
32. 32.🔺 A current of 20 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
33. 33.🔍 An object is 187 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
34. 34.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they all go out (b) they get dimmer (c) they keep glowing (d) they explode
35. 35.🔍 Which is the odd one out? (a) stop if a part gets hot (b) stay away from pylons (c) build with an adult near (d) use mains for a project
36. 36.✏️ Why do engineers draw circuits with symbols? (a) symbols are heavier (b) to hide the circuit (c) quick and clear for all (d) to make it colourful
37. 37.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 590 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
38. 38.🔍 Which is the odd one out? (a) a steel coin (b) a paper strip (c) a steel spoon (d) a brass key
39. 39.True or false: “a break stops every bulb” is true of a series circuit. (a) True (b) False
40. 40.Which of these is a conductor? (a) a woollen thread (b) a dry cork (c) a plastic ruler (d) an iron nail

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