Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 310 · 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.⏱️ How many milliseconds is a wait of 1.8 seconds?
2. 2.🧮 Adding another resistor in series makes the total resistance … (a) stay the same (b) smaller (c) bigger (d) zero
3. 3.Which of these is an IoT device? (a) a battery torch (b) a Wi-Fi smart plug (c) a pencil sharpener (d) a wind-up clock
4. 4.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) by Wi-Fi (c) in parallel (d) in series
5. 5.🔺 A current of 40 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
6. 6.Which of these is measured in amperes (A)? (a) power (b) voltage (c) how much a part resists (d) the flow of charge
7. 7.True or false: if the switch is OFF, the circuit is closed and current flows. (a) False (b) True
8. 8.🤖 Microcontroller or laptop: which one runs one small program? (a) laptop (b) microcontroller
9. 9.Which of these gives us electricity? (a) a washing machine (b) an air conditioner (c) a bicycle dynamo (d) a water pump
10. 10.True or false: a steel spoon is an insulator. (a) False (b) True
11. 11.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I × R (c) V = R ÷ I (d) V = I ÷ R
12. 12.🔁 x = 3
    repeat 1 time { x = x × 2 }
    What is x at the end?
13. 13.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
14. 14.Which of these is a conductor? (a) a rubber band (b) a graphite rod (c) a rubber eraser (d) a glass marble
15. 15.True or false: on an LED, the shorter leg is the anode (+). (a) True (b) False
16. 16.🤖 “if (A AND B)” is true when … (a) both are false (b) only B is true (c) only A is true (d) both A and B are true
17. 17.Which of these mainly gives out heat? (a) a buzzer (b) an electric kettle (c) a torch (d) a siren
18. 18.True or false: a steel coin is an insulator. (a) True (b) False
19. 19.🧮 A 16 V battery is joined to 10 Ω and 6 Ω resistors in series. What current flows (in amperes)? =
20. 20.🤖 if (light < 500) { lamp ON } else { lamp OFF }
    The light sensor reads 507. What happens? (a) lamp OFF (b) lamp ON
21. 21.🔌 Is a steel coin a conductor or an insulator? (a) a conductor (b) an insulator
22. 22.🧮 Two equal 10 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
23. 23.True or false: the ammeter is joined in series. (a) False (b) True
24. 24.🔁 What does a variable do in a program? (a) measures light (b) blinks an LED (c) joins two wires (d) stores a value
25. 25.📶 How many states can a digital pin have? (a) one (b) ten (c) a thousand (d) two
26. 26.Which of these is a risky habit? (a) share camera links (b) read app permissions (c) share only needed data (d) install software updates
27. 27.⚡ A home appliance on the 230 V mains takes 4 A. What is its power (in watts)?
28. 28.🌈 A resistor has the colour bands grey, brown, orange. What is its value (in ohms)?
29. 29.True or false: “a single current path” is true of a series circuit. (a) True (b) False
30. 30.True or false: a school bell mainly makes sound. (a) True (b) False
31. 31.🔺 A 24 V supply is joined across an 8 Ω resistor. What current flows (in amperes)? =
32. 32.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the switch is ON (d) the switch is OFF
33. 33.🔺 A current of 20 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
34. 34.Which of these is the input? (a) a buzzer beeps (b) the pump turns on (c) an alert on the phone (d) a soil moisture reading
35. 35.True or false: a circle with V inside is the symbol for a voltmeter. (a) False (b) True
36. 36.💡 Why does an LED need a resistor in series? (a) to change its colour (b) to store charge (c) to limit the current (d) to make it brighter
37. 37.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 5 % (c) 50 % (d) 25 %
38. 38.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) the else part (c) neither part (d) the if part
39. 39.Which of these is the input? (a) decide if soil is dry (b) the fan starts (c) a light level reading (d) count button presses
40. 40.🧮 A 3.75 V battery is joined to 3 Ω and 12 Ω resistors in series. What current flows (in amperes)? =

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