Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 296 · 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.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 ampere (c) 1 volt (d) 1 watt
2. 2.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = V + I (c) R = I ÷ V (d) R = V ÷ I
3. 3.True or false: a circle with an X in it is the symbol for a bulb. (a) False (b) True
4. 4.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put an iron nail across the gap. Does the bulb glow? (a) Yes (b) No
5. 5.💡 5 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulb 5 is taken out of its holder. How many bulbs glow?
6. 6.🔍 Which is the odd one out? (a) set up with a parent (b) cover unused cameras (c) keep factory passwords (d) log out of shared phones
7. 7.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
8. 8.🌐 How does a home IoT device usually send its data to the app? (a) by post (b) through a candle (c) over Wi-Fi (d) by shouting
9. 9.🔌 Is a metal paper clip a conductor or an insulator? (a) an insulator (b) a conductor
10. 10.🌐 In an IoT system, which part stores data online? (a) actuator (b) sensor (c) cloud server (d) microcontroller
11. 11.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they all go out (c) they get dimmer (d) they keep glowing
12. 12.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) diode (b) LED (c) wire (d) switch
13. 13.🌐 A soil sensor sends a reading to an app every 10 minutes. How many readings arrive in 6 hours?
14. 14.🔍 Which is the odd one out? (a) a temperature sensor (b) a motion sensor (c) a buzzer (d) a sound sensor
15. 15.⚠️ Which power source should children use for electronics projects? (a) a mains extension board (b) an inverter socket (c) a wall socket (d) a small battery pack
16. 16.True or false: to accept every permission is a good habit. (a) False (b) True
17. 17.🔋 6 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
18. 18.🔍 Which is the odd one out? (a) a Wi-Fi weather station (b) a plain wall switch (c) a Wi-Fi smart plug (d) a Wi-Fi doorbell camera
19. 19.🔁 x = 4
    repeat 5 times { x = x × 2 }
    What is x at the end?
20. 20.True or false: to share the Wi-Fi key is a risky habit. (a) False (b) True
21. 21.True or false: to keep factory passwords is a good habit. (a) True (b) False
22. 22.Which of these is not safe? (a) take cells out after use (b) keep drinks far away (c) fly kites in open fields (d) fly a kite near wires
23. 23.✏️ Why do engineers draw circuits with symbols? (a) to hide the circuit (b) quick and clear for all (c) symbols are heavier (d) to make it colourful
24. 24.⚠️ Is it safe to build with an adult near? (a) not safe (b) safe
25. 25.💡 A red LED uses 2 V and should get 10 mA. It runs from a 9 V supply. What resistor (in ohms) is needed in series?
26. 26.🔘 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
27. 27.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
28. 28.🔘 Which kind of switch springs back when let go? (a) a push button (b) a tilt switch (c) a slide switch (d) a reed switch
29. 29.True or false: on a cell, “the flat end” means the + (positive) end. (a) False (b) True
30. 30.Which of these is true of a series circuit? (a) a single current path (b) one out, the rest glow (c) each gets the full volts (d) used in house wiring
31. 31.True or false: “a button: pressed or not” is a digital signal. (a) True (b) False
32. 32.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 410 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
33. 33.⏱️ repeat 7 times { buzzer ON; wait 800 ms; buzzer OFF; wait 1000 ms }
    How many milliseconds does this take in all?
34. 34.⚠️ Is it safe to use a cable with cuts? (a) not safe (b) safe
35. 35.🧮 Four equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
36. 36.🔁 count = 0
    while (count < 8) { count = count + 2 }
    How many times does the loop run?
37. 37.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 100 ms }
    How many times does the LED blink in 5 seconds?
38. 38.⏱️ loop forever { LED ON; wait 300 ms; LED OFF; wait 650 ms }
    How many milliseconds does one blink (ON + OFF) take?
39. 39.🧩 Which component makes a beeping sound? (a) potentiometer (b) buzzer (c) LDR (d) motor
40. 40.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a program (d) a battery

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