Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 315 · 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.📶 On a 5 V board, a pin set HIGH gives about … (a) 230 V (b) 5 V (c) 50 V (d) 0 V
2. 2.True or false: “a tilt switch: on or off” is a digital signal. (a) True (b) False
3. 3.True or false: on a cell, “the flat end” means the − (negative) end. (a) True (b) False
4. 4.🌈 A resistor has the colour bands green, yellow, red. What is its value in kilo-ohms (kΩ)? =
5. 5.🔍 Which is the odd one out? (a) an alert on the phone (b) count button presses (c) the fan starts (d) the pump turns on
6. 6.⏱️ What does “wait 500 ms” do? (a) pauses for half a second (b) waits 500 seconds (c) turns the LED off (d) blinks 500 times
7. 7.⚡ A home appliance on the 230 V mains takes 0.5 A. What is its power (in watts)?
8. 8.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) True (b) False
9. 9.🔍 Which is the odd one out? (a) a Wi-Fi weather station (b) a wind-up clock (c) a plain wall switch (d) a battery torch
10. 10.🔍 Which is the odd one out? (a) use daylight to read (b) iron one shirt at a time (c) leave the TV on standby (d) leave fridge door open
11. 11.🧮 Three equal 75 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
12. 12.⏱️ loop forever { LED ON; wait 850 ms; LED OFF; wait 150 ms }
    How many times does the LED blink in 3 seconds?
13. 13.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) the if part (c) the else part (d) neither part
14. 14.🧩 A capacitor in a circuit can … (a) spin a wheel (b) store charge briefly (c) make light (d) measure heat
15. 15.🔺 A current of 10 mA flows when 1.2 V is joined across a resistor. What is its resistance (in ohms)?
16. 16.Which of these is measured in watts (W)? (a) voltage (b) how much a part resists (c) resistance (d) power
17. 17.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 140 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
18. 18.True or false: an electric drill mainly makes movement. (a) False (b) True
19. 19.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) False (b) True
20. 20.True or false: a fuse lets current go one way. (a) True (b) False
21. 21.🗺️ Before building a project, what should you write down first? (a) the final price (b) the box colour (c) inputs and outputs (d) nothing at all
22. 22.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a servo motor (c) a pump (d) a motor
23. 23.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a capacitor (c) a resistor (d) a diode
24. 24.Which of these is safe? (a) build with an adult near (b) open a phone charger (c) throw cells in a fire (d) climb an electric pole
25. 25.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) a wire has come loose (d) the loop is complete
26. 26.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
27. 27.True or false: “HIGH or LOW only” is a digital signal. (a) False (b) True
28. 28.🔺 A 22.5 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
29. 29.True or false: a long and a short line is the symbol for a cell. (a) True (b) False
30. 30.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) two (c) one (d) none
31. 31.💡 Why does an LED need a resistor in series? (a) to make it brighter (b) to limit the current (c) to change its colour (d) to store charge
32. 32.🔋 What is a battery? (a) a switch with a lid (b) one single wire (c) a kind of bulb (d) two or more cells joined
33. 33.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) only one (c) none (d) it does not matter
34. 34.🔁 x = 2
    repeat 1 time { x = x × 2 }
    What is x at the end?
35. 35.💡 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?
36. 36.🔍 Which sensor would you use to stop a robot near walls? (a) a sound sensor (b) a distance sensor (c) a soil moisture sensor (d) a temperature sensor
37. 37.What does the microcontroller do? (a) reads values, decides (b) acts on a command (c) measures the real world (d) shows data to you
38. 38.🔁 What does a variable do in a program? (a) blinks an LED (b) joins two wires (c) measures light (d) stores a value
39. 39.Which of these is the input? (a) a button press (b) count button presses (c) an LED lights up (d) compare with a limit
40. 40.True or false: to set up with a parent is a good habit. (a) False (b) True

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