Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 981 · 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.💡 5 identical bulbs are joined in series with a 20 V battery (ideal wires). How many volts does each bulb get? =
2. 2.🧩 Which component limits the current? (a) diode (b) buzzer (c) resistor (d) LED
3. 3.🗺️ In an input → process → output plan, is “a temperature reading” the input, the process or the output? (a) output (b) input (c) process
4. 4.✏️ In a circuit diagram, which part is drawn as two or more cell symbols? (a) junction (b) battery (c) wire (d) switch
5. 5.🔐 Is it a good or a risky habit to read app permissions? (a) risky habit (b) good habit
6. 6.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
7. 7.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) battery (b) motor (c) junction (d) resistor
8. 8.🔋 Does a refrigerator give electricity or use electricity? (a) uses electricity (b) gives electricity
9. 9.🌐 Each reading a sensor sends is 20 bytes. How many bytes do 160 readings take?
10. 10.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 5 V supply. What current flows (in mA)?
11. 11.✏️ In a circuit diagram, wires are usually drawn as … (a) dotted circles (b) straight lines (c) wavy lines (d) little stars
12. 12.⚠️ Is it safe to fly a kite near wires? (a) not safe (b) safe
13. 13.🔺 A 4.4 V supply is joined across a 220 Ω resistor. What current flows (in milliamperes, mA)?
14. 14.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 360 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
15. 15.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 7 seconds?
16. 16.🔢 To get a sensor reading onto a phone, which is the LAST step? (a) the sensor measures (b) the board reads it (c) the app shows it (d) it is sent by Wi-Fi
17. 17.True or false: a circle with A inside is the symbol for a battery. (a) False (b) True
18. 18.⏱️ repeat 6 times { buzzer ON; wait 900 ms; buzzer OFF; wait 500 ms }
    How many milliseconds does this take in all?
19. 19.⚠️ Which power source should children use for electronics projects? (a) a small battery pack (b) an inverter socket (c) a mains extension board (d) a wall socket
20. 20.Which of these is measured in amperes (A)? (a) energy used each second (b) voltage (c) current (d) power
21. 21.True or false: to set the AC to 24 °C saves electricity. (a) True (b) False
22. 22.🔌 A gap of dry air between two wires acts as … (a) a cell (b) a conductor (c) a switch that is ON (d) an insulator
23. 23.🔺 A 12 V supply is joined across a 300 Ω resistor. What current flows (in milliamperes, mA)?
24. 24.Which of these is a good habit? (a) tap unknown app links (b) share camera links (c) accept every permission (d) set a strong password
25. 25.🔋 What is a battery? (a) a kind of bulb (b) two or more cells joined (c) a switch with a lid (d) one single wire
26. 26.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) True (b) False
27. 27.True or false: to run fans in empty rooms saves electricity. (a) True (b) False
28. 28.True or false: a laptop has a built-in keyboard. (a) False (b) True
29. 29.True or false: a digital thermometer usually has a microcontroller inside. (a) False (b) True
30. 30.🌈 Which band is read first on a resistor? (a) the one nearest an end (b) the gold band (c) any band (d) the widest gap
31. 31.🔋 Does a wind turbine give electricity or use electricity? (a) uses electricity (b) gives electricity
32. 32.🔁 What must there be for a current to flow? (a) a broken path (b) one loose end (c) a plastic gap (d) a complete loop
33. 33.⚠️ Is it safe to touch a fallen wire? (a) safe (b) not safe
34. 34.🔋 Cells joined + to − in a row (series) give … (a) a bigger voltage (b) the same voltage (c) a smaller voltage (d) no voltage
35. 35.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
36. 36.🔘 What does a switch do in a circuit? (a) makes electricity (b) stores current (c) opens or closes the loop (d) changes the voltage
37. 37.🔺 In the V-I-R triangle, how do we find R? (a) R = V + I (b) R = V × I (c) R = V ÷ I (d) R = I ÷ V
38. 38.🔘 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
39. 39.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) share it with friends (b) ask a parent first (c) type it all in (d) post it online
40. 40.💡 Does it save or waste electricity to use daylight to read? (a) saves electricity (b) wastes electricity

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