Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 148 · 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.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) stays the same (c) becomes zero (d) gets bigger
2. 2.True or false: a motor turns a fan or wheels. (a) False (b) True
3. 3.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a motor (c) an LED (d) a buzzer
4. 4.⏱️ repeat 5 times { buzzer ON; wait 800 ms; buzzer OFF; wait 900 ms }
   How many milliseconds does this take in all?
5. 5.💡 A red LED uses 2 V and should get 25 mA. It runs from a 12 V supply. What resistor (in ohms) is needed in series?
6. 6.Which of these is an input? (a) a light sensor (b) a buzzer (c) a speaker (d) a water pump
7. 7.🔘 Two switches are in series. When does the bulb glow? (a) when both are OFF (b) when either is ON (c) never (d) when both are ON
8. 8.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) True (b) False
9. 9.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 100 ms }
   How many times does the LED blink in 10 seconds?
10. 10.🔘 Which kind of switch closes when tipped over? (a) a toggle switch (b) a reed switch (c) a tilt switch (d) a push button
11. 11.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
12. 12.Which of these is safe? (a) dry your hands first (b) poke things in a socket (c) touch a switch when wet (d) touch a fallen wire
13. 13.True or false: one tall, one short bar is the symbol for a diode. (a) False (b) True
14. 14.🔗 Series or parallel circuit: “own switch for each bulb”? (a) series (b) parallel
15. 15.🔋 How many 1.5 V cells must be joined in series to give 12 V?
16. 16.🧮 Two equal 470 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
17. 17.💡 In a series circuit, how many paths does the current have? (a) one (b) two (c) none (d) one for each bulb
18. 18.What does the cloud server do? (a) reads values, decides (b) stores data online (c) measures the real world (d) shows data to you
19. 19.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
20. 20.🧮 Two resistors in parallel give a total that is … (a) their sum (b) always zero (c) less than either one (d) more than either one
21. 21.🔍 An object is 119 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
22. 22.True or false: a tilt switch stays where you flip it. (a) True (b) False
23. 23.🧩 Which component glows using little power? (a) LED (b) resistor (c) LDR (d) potentiometer
24. 24.Which of these is a good habit? (a) accept every permission (b) share camera links (c) reuse one password (d) cover unused cameras
25. 25.⚡ A device works on 24 V and takes 2 A. What is its power (in watts)? =
26. 26.💡 4 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?
27. 27.🔋 6 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
28. 28.💡 What does LED stand for? (a) light-emitting diode (b) large electric dial (c) light energy dial (d) low energy device
29. 29.True or false: a microcontroller runs one small program. (a) True (b) False
30. 30.🌈 Which band is read first on a resistor? (a) the gold band (b) any band (c) the one nearest an end (d) the widest gap
31. 31.🔁 x = 3
    repeat 1 time { x = x × 2 }
    What is x at the end?
32. 32.📏 How many milliamperes (mA) is 0.15 A?
33. 33.True or false: a plain rectangle is the symbol for a resistor. (a) False (b) True
34. 34.💡 3 identical bulbs are in parallel and each bulb has its own switch on its path. 2 of the switches are OFF and the rest are ON. How many bulbs glow?
35. 35.✏️ In a circuit diagram, which part is drawn as a straight line? (a) resistor (b) cell (c) wire (d) voltmeter
36. 36.What does a push button do? (a) stays where you flip it (b) flips up or down (c) closes near a magnet (d) springs back when let go
37. 37.🔺 In the V-I-R triangle, how do we find I? (a) I = V × R (b) I = V + R (c) I = R ÷ V (d) I = V ÷ R
38. 38.🔐 Which is the strongest password for a home smart camera? (a) Tiger#Lamp42!Moon (b) admin (c) 123456 (d) password
39. 39.Which job needs a servo motor? (a) spin a robot’s wheels (b) move water to plants (c) beep an alarm (d) turn to an exact angle
40. 40.📏 Which unit measures the push of a cell? (a) volt (V) (b) ampere (A) (c) ohm (Ω) (d) watt (W)

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