Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 214 · 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.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a metal paper clip across the gap. Does the bulb glow? (a) No (b) Yes
2. 2.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the switch (b) the glass (c) the filament (d) the base
3. 3.🔁 What does “count = count + 1” do? (a) adds 1 to count (b) prints 1 (c) takes 1 away (d) sets count to 1
4. 4.🧩 Which component turns a fan or wheels? (a) capacitor (b) transistor (c) motor (d) LED
5. 5.🤖 Microcontroller or laptop: which one uses very little power? (a) laptop (b) microcontroller
6. 6.⚡ A device works on 24 V and takes 1.5 A. What is its power (in watts)? =
7. 7.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
8. 8.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 410 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
9. 9.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
10. 10.🤖 if (sound > 60) { red LED ON } else { green LED ON }
    The sound sensor reads 80. What happens? (a) red LED ON (b) green LED ON
11. 11.🔌 Is a water pump an input or an output for a microcontroller? (a) input (b) output
12. 12.🤖 How does a new program get onto a microcontroller board? (a) uploaded over USB (b) typed on the chip (c) sent by sound (d) drawn with a pen
13. 13.True or false: “a break stops every bulb” is true of a parallel circuit. (a) True (b) False
14. 14.🔐 Is it a good or a risky habit to set a strong password? (a) good habit (b) risky habit
15. 15.True or false: a microcontroller runs one small program. (a) True (b) False
16. 16.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) wavy lines (c) dotted circles (d) straight lines
17. 17.🗺️ In an input → process → output plan, is “decide if soil is dry” the input, the process or the output? (a) input (b) process (c) output
18. 18.Which drawing is the symbol for a wire? (a) one tall, one short bar (b) a straight line (c) a circle with M inside (d) two or more cell symbols
19. 19.🔋 2 identical 1.2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
20. 20.Which drawing is the symbol for a junction? (a) a circle with a cross (b) a circle with V inside (c) a dot where wires meet (d) many long-short pairs
21. 21.🤖 When the main loop of a microcontroller program ends, what happens? (a) the board breaks (b) it starts again (c) it stops forever (d) it deletes itself
22. 22.🔺 A current of 10 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
23. 23.⚡ What does a tube light mainly change electricity into? (a) sound (b) movement (c) heat (d) light
24. 24.What does a buzzer do? (a) lets current go one way (b) beeps for an alarm (c) is a resistance knob (d) blows if current is high
25. 25.💡 5 identical bulbs are in parallel and each one takes 1.5 A. What total current (in amperes) comes from the battery? =
26. 26.📏 In the water-pipe picture of a circuit, resistance is like … (a) the flow of water (b) a bigger tank (c) a narrow pipe (d) the water pressure
27. 27.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I ÷ R (c) V = R ÷ I (d) V = I × R
28. 28.🧮 Three equal 60 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
29. 29.🔁 What do we call a circuit with a break in it? (a) a series circuit (b) a closed circuit (c) an open circuit (d) a full circuit
30. 30.⚠️ Which power source should children use for electronics projects? (a) a small battery pack (b) a wall socket (c) an inverter socket (d) a mains extension board
31. 31.⏱️ repeat 2 times { buzzer ON; wait 500 ms; buzzer OFF; wait 700 ms }
    How many milliseconds does this take in all?
32. 32.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
33. 33.🔍 Which is the odd one out? (a) check if temp > 30 (b) compare with a limit (c) the pump turns on (d) decide if soil is dry
34. 34.🔋 Does a mobile phone give electricity or use electricity? (a) uses electricity (b) gives electricity
35. 35.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) neither line (c) both lines (d) the shorter line
36. 36.🌐 Is a paper calendar an IoT device? (a) an IoT device (b) not an IoT device
37. 37.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) turns the LED off (c) blinks 500 times (d) pauses for half a second
38. 38.🔺 A current of 0.25 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
39. 39.🔘 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 ON, C is OFF and D is ON. Does the bulb glow? (a) Yes (b) No
40. 40.🧮 A 12 V battery is joined to 8 Ω and 4 Ω resistors in series. What current flows (in amperes)? =

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