Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 222 · 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.🔋 Does a wind turbine give electricity or use electricity? (a) gives electricity (b) uses electricity
2. 2.🔦 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) No (b) Yes
3. 3.🧮 A 33 Ω resistor is joined in series with two equal 20 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
4. 4.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
5. 5.💡 5 identical bulbs are joined in parallel across a 9 V battery (ideal wires). How many volts does each bulb get? =
6. 6.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) a buzzer (c) an LED (d) a motor
7. 7.⚡ A 1.5 W device works on 3 V. What current does it take (in amperes)? =
8. 8.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a brass key across the gap. Does the bulb glow? (a) No (b) Yes
9. 9.What does a toggle switch do? (a) springs back when let go (b) closes when tipped over (c) stays where you flip it (d) closes near a magnet
10. 10.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. A gap in one wire is bridged by a steel coin. Does the bulb glow? (a) Yes (b) No
11. 11.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
12. 12.Which of these usually has a microcontroller inside? (a) a hand pump (b) a TV remote (c) a wind-up toy (d) a bicycle bell
13. 13.Which of these mainly makes movement? (a) a school bell (b) a traffic signal (c) an electric drill (d) a siren
14. 14.⏱️ A program says “wait 7250 ms”. How many seconds is that? =
15. 15.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) Yes (b) No
16. 16.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) an input (d) a power source
17. 17.⚡ Which formula gives electric power? (a) P = V + I (b) P = I ÷ V (c) P = V ÷ I (d) P = V × I
18. 18.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) wavy lines (c) dotted circles (d) little stars
19. 19.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 1 second?
20. 20.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is OFF, B is OFF and C is ON. Does the bulb glow? (a) Yes (b) No
21. 21.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 13 °C. What is shown? (a) Warm (b) Hot (c) Cool
22. 22.🧮 A 50 Ω resistor is joined in series with two equal 470 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
23. 23.💡 In a series circuit, how many paths does the current have? (a) one (b) none (c) two (d) one for each bulb
24. 24.🔢 To plan an electronics project, which is the LAST step? (a) list inputs and outputs (b) test it and fix it (c) draw the circuit diagram (d) pick a problem to solve
25. 25.Which drawing is the symbol for an LED? (a) two or more cell symbols (b) a circle with an X in it (c) a line lifted at a gap (d) triangle, bar and arrows
26. 26.🔺 A current of 50 mA flows when 15 V is joined across a resistor. What is its resistance (in ohms)?
27. 27.💡 4 identical bulbs are in parallel and each one takes 0.2 A. What total current (in amperes) comes from the battery? =
28. 28.🔋 4 identical 3 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
29. 29.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a slide switch (c) a tilt switch (d) a reed switch
30. 30.📏 Which unit measures resistance? (a) ampere (A) (b) volt (V) (c) watt (W) (d) ohm (Ω)
31. 31.🔍 Which is the odd one out? (a) ignore update messages (b) keep factory passwords (c) post your live location (d) turn off unused gadgets
32. 32.⏱️ How many milliseconds is a wait of 3.2 seconds?
33. 33.🔗 Series or parallel circuit: “each gets the full volts”? (a) parallel (b) series
34. 34.True or false: a microcontroller runs many apps at once. (a) True (b) False
35. 35.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
36. 36.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
37. 37.📏 Which unit measures current? (a) watt (W) (b) ohm (Ω) (c) ampere (A) (d) volt (V)
38. 38.True or false: a push button closes near a magnet. (a) False (b) True
39. 39.True or false: a tube light mainly makes sound. (a) True (b) False
40. 40.🗺️ Before building a project, what should you write down first? (a) inputs and outputs (b) the final price (c) nothing at all (d) the box colour

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