Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 618 · 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.True or false: “many paths for current” is true of a parallel circuit. (a) True (b) False
2. 2.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) a fuse (d) an input
3. 3.True or false: a buzzer mainly makes sound. (a) True (b) False
4. 4.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) the shorter line (c) both lines (d) the longer line
5. 5.Which of these is a good habit? (a) tap unknown app links (b) post your live location (c) change default passwords (d) ignore update messages
6. 6.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a dry cork across the gap. Does the bulb glow? (a) Yes (b) No
7. 7.True or false: “one out, the rest glow” is true of a parallel circuit. (a) True (b) False
8. 8.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
9. 9.🔋 Identical cells side by side (in parallel) give … (a) double the voltage (b) no voltage (c) half the voltage (d) the same voltage
10. 10.⚡ A home appliance on the 230 V mains takes 0.5 A. What is its power (in watts)?
11. 11.Which of these is measured in volts (V)? (a) the flow of charge (b) voltage (c) current (d) energy used each second
12. 12.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 volt (c) 1 watt (d) 1 kilowatt-hour (kWh)
13. 13.True or false: to keep an incubator warm, use a rain sensor. (a) True (b) False
14. 14.🔺 A current of 1 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
15. 15.🔍 Which is the odd one out? (a) stop if a part gets hot (b) touch a switch when wet (c) touch a fallen wire (d) fly a kite near wires
16. 16.True or false: if the switch is OFF, the circuit is open and no current flows. (a) True (b) False
17. 17.🔘 Which kind of switch works only while pressed? (a) a tilt switch (b) a push button (c) a reed switch (d) a toggle switch
18. 18.🔋 What should you do with used-up cells? (a) give them for recycling (b) bury them in soil (c) cut them open (d) throw them in a fire
19. 19.🔢 To run one loop of a plant-watering program, which is the LAST step? (a) switch the pump on/off (b) wait a few seconds (c) compare with the limit (d) read the soil sensor
20. 20.🔌 Is a temperature sensor an input or an output for a microcontroller? (a) input (b) output
21. 21.🔌 Which part of a screwdriver should an electrician hold? (a) the bare end (b) the steel shaft (c) the plastic handle (d) the metal tip
22. 22.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is ON and C is ON. Does the bulb glow? (a) No (b) Yes
23. 23.🔋 3 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)? =
24. 24.🔺 A 1.2 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
25. 25.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 60 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
26. 26.True or false: “a break stops every bulb” is true of a parallel circuit. (a) True (b) False
27. 27.🔍 Which is the odd one out? (a) an electric toy car (b) a mixer grinder (c) a tube light (d) a table fan
28. 28.Which of these is measured in watts (W)? (a) resistance (b) power (c) current (d) voltage
29. 29.🌈 A resistor has the colour bands yellow, black, black. What is its value (in ohms)?
30. 30.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) wavy lines (c) dotted circles (d) straight lines
31. 31.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
32. 32.🌈 A resistor has the colour bands yellow, red, red. What is its value in kilo-ohms (kΩ)? =
33. 33.🔁 What does a variable do in a program? (a) stores a value (b) blinks an LED (c) joins two wires (d) measures light
34. 34.🔺 A 7.5 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
35. 35.Which of these is not an IoT device? (a) a smart energy meter (b) a Wi-Fi doorbell camera (c) an app-controlled bulb (d) a wind-up clock
36. 36.🧾 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?
37. 37.🧮 An 8 V battery is joined to 10 Ω and 6 Ω resistors in series. What current flows (in amperes)? =
38. 38.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in parallel (b) not joined (c) by Wi-Fi (d) in series
39. 39.True or false: a wind-up toy usually has a microcontroller inside. (a) False (b) True
40. 40.🔘 When a switch is ON, the circuit is … (a) closed (b) open (c) broken (d) cut

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