Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 514 · 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 soil sensor sends a reading to an app every 30 minutes. How many readings arrive in 6 hours?
2. 2.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the filament (b) the base (c) the glass (d) the switch
3. 3.🔗 Series or parallel circuit: “many paths for current”? (a) parallel (b) series
4. 4.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) False (b) True
5. 5.💡 6 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 6 is taken out of its holder. How many bulbs glow?
6. 6.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) battery (b) diode (c) resistor (d) motor
7. 7.⚠️ Is it safe to stay away from pylons? (a) not safe (b) safe
8. 8.📏 Which unit measures the push of a cell? (a) watt (W) (b) ohm (Ω) (c) volt (V) (d) ampere (A)
9. 9.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   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
10. 10.🔋 Does a mobile phone give electricity or use electricity? (a) uses electricity (b) gives electricity
11. 11.💡 A battery lights 2 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
12. 12.🧩 Which part changes electrical energy into sound? (a) a diode (b) a capacitor (c) a resistor (d) a buzzer
13. 13.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) post it online (b) ask a parent first (c) type it all in (d) share it with friends
14. 14.💡 An LED is joined to a 9 V battery with no resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) lights up (b) does not light (c) may burn out
15. 15.🔁 total = 0
    for i = 1 to 5 { total = total + i }
    What is total at the end?
16. 16.⚠️ Is it safe to use small battery cells? (a) not safe (b) safe
17. 17.🔁 repeat 2 times { repeat 6 times { beep } }
    How many beeps are there?
18. 18.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
19. 19.🧮 Resistors of 220 Ω and 470 Ω are joined in series. What is the total resistance (in ohms)?
20. 20.What does a toggle switch do? (a) slides side to side (b) works only while pressed (c) closes when tipped over (d) stays where you flip it
21. 21.True or false: a laptop runs many apps at once. (a) False (b) True
22. 22.🔁 x = 3
    repeat 4 times { x = x × 2 }
    What is x at the end?
23. 23.📏 How many milliamperes (mA) make 1 ampere? (a) 100 (b) 10 (c) 1000 (d) 60
24. 24.🔍 Which is the odd one out? (a) a ceramic cup (b) a glass marble (c) a safety pin (d) a cotton thread
25. 25.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) junction (b) wire (c) capacitor (d) cell
26. 26.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a servo motor (c) a motor (d) a display
27. 27.🔌 Is a brass key a conductor or an insulator? (a) a conductor (b) an insulator
28. 28.True or false: a microcontroller has no screen of its own. (a) False (b) True
29. 29.Which of these is measured in watts (W)? (a) resistance (b) energy used each second (c) the push of a cell (d) the flow of charge
30. 30.🔺 A current of 1.5 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
31. 31.True or false: a toggle switch closes near a magnet. (a) True (b) False
32. 32.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
33. 33.Which of these is a good habit? (a) share camera links (b) tap unknown app links (c) ignore update messages (d) install software updates
34. 34.💡 Why does an LED need a resistor in series? (a) to store charge (b) to make it brighter (c) to limit the current (d) to change its colour
35. 35.🤖 if (moisture < 50) { pump ON } else { pump OFF }
    The soil moisture sensor reads 51 %. What happens? (a) pump OFF (b) pump ON
36. 36.What does a resistor do? (a) senses how hot it is (b) has coloured bands (c) makes a beeping sound (d) boosts a small signal
37. 37.🔘 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 ON and C is ON. Does the bulb glow? (a) No (b) Yes
38. 38.🤖 Does a bicycle bell usually have a microcontroller inside? (a) Yes (b) No
39. 39.🔍 Which is the odd one out? (a) a plastic straw (b) an iron nail (c) a graphite rod (d) a steel spoon
40. 40.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 10 (b) 1000 (c) 100 (d) 1024

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