Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 427 · 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.📏 Which unit measures voltage? (a) ampere (A) (b) ohm (Ω) (c) watt (W) (d) volt (V)
2. 2.🔁 What does “count = count + 1” do? (a) sets count to 1 (b) prints 1 (c) takes 1 away (d) adds 1 to count
3. 3.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 150 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
4. 4.Which job needs a motion sensor? (a) spot someone walking in (b) measure classroom noise (c) warn of a gas leak (d) make a parking alarm
5. 5.💡 3 identical bulbs are in parallel and each bulb has its own switch on its path. 1 of the switches is OFF and the rest are ON. How many bulbs glow?
6. 6.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 7 HIGH
   set pin 7 HIGH
   set pin 8 HIGH
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) OFF (b) ON
7. 7.⏱️ loop forever { LED ON; wait 650 ms; LED OFF; wait 300 ms }
   How many milliseconds does one blink (ON + OFF) take?
8. 8.🔍 Which is the odd one out? (a) share the Wi-Fi key (b) keep factory passwords (c) read app permissions (d) ignore update messages
9. 9.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
10. 10.🧾 Which lamp gives the same light for the least power? (a) an LED lamp (b) a candle (c) an oil lamp (d) a filament bulb
11. 11.🔐 Is it a good or a risky habit to turn off unused gadgets? (a) good habit (b) risky habit
12. 12.🔋 Does a generator give electricity or use electricity? (a) uses electricity (b) gives electricity
13. 13.🧾 A 250 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
14. 14.Which of these is not safe? (a) use small battery cells (b) stay away from pylons (c) keep drinks far away (d) use mains for a project
15. 15.Which drawing is the symbol for a switch? (a) a line lifted at a gap (b) a circle with A inside (c) triangle, bar and arrows (d) triangle against a bar
16. 16.🔐 Is it a good or a risky habit to log out of shared phones? (a) good habit (b) risky habit
17. 17.Which of these means the circuit is closed? (a) the switch is OFF (b) the bulb is unscrewed (c) a wire has come loose (d) the switch is ON
18. 18.🔍 Which is the odd one out? (a) a tube light (b) a room heater (c) a traffic signal (d) an LED lamp
19. 19.True or false: a fuse limits the current. (a) True (b) False
20. 20.🔐 Is it a good or a risky habit to install software updates? (a) risky habit (b) good habit
21. 21.Which of these mainly makes movement? (a) a water heater (b) a rice cooker (c) a loudspeaker (d) a mixer grinder
22. 22.True or false: to ignore update messages is a good habit. (a) True (b) False
23. 23.🔌 Is a water pump an input or an output for a microcontroller? (a) output (b) input
24. 24.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 2 minutes?
25. 25.🔺 An 18.8 V supply is joined across a 470 Ω resistor. What current flows (in milliamperes, mA)?
26. 26.🧮 Three equal 15 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
27. 27.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) resistor (b) diode (c) switch (d) voltmeter
28. 28.Which drawing is the symbol for a voltmeter? (a) many long-short pairs (b) one tall, one short bar (c) a circle with V inside (d) a circle with M inside
29. 29.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is ON and B is ON. Does the bulb glow? (a) No (b) Yes
30. 30.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V + I (c) P = V ÷ I (d) P = V × I
31. 31.⚠️ Who should be with you when you build a circuit? (a) nobody (b) a younger child (c) a stranger online (d) a trusted adult
32. 32.🔁 What does a variable do in a program? (a) blinks an LED (b) stores a value (c) measures light (d) joins two wires
33. 33.⚠️ Which power source should children use for electronics projects? (a) an inverter socket (b) a wall socket (c) a mains extension board (d) a small battery pack
34. 34.🔁 repeat 2 times { repeat 6 times { beep } }
    How many beeps are there?
35. 35.Which of these is not safe? (a) use small battery cells (b) take cells out after use (c) build with an adult near (d) touch a fallen wire
36. 36.🧮 A 1.75 V battery is joined to 2 Ω and 5 Ω resistors in series. What current flows (in amperes)? =
37. 37.🔍 Which is the odd one out? (a) a school bell (b) a siren (c) a loudspeaker (d) a ceiling fan
38. 38.What does a thermistor do? (a) limits the current (b) senses how hot it is (c) is a resistance knob (d) makes things spin
39. 39.Which of these is measured in amperes (A)? (a) the push of a cell (b) resistance (c) power (d) the flow of charge
40. 40.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) wire (b) battery (c) bulb (d) resistor

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