Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 827 · 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 pin that reads a push button is set as … (a) a battery (b) an input (c) an output (d) a resistor
2. 2.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) closed (b) open
3. 3.⚡ A device works on 12 V and takes 1 A. What is its power (in watts)? =
4. 4.⚡ What does an electric drill mainly change electricity into? (a) heat (b) movement (c) light (d) sound
5. 5.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a fuse (d) a power source
6. 6.🔺 A current of 25 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
7. 7.⚡ Power tells us … (a) energy used each second (b) the colour of light (c) the size of a cell (d) the length of a wire
8. 8.🌈 In the resistor colour code, which number does green stand for?
9. 9.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
10. 10.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the if part (b) neither part (c) the else part (d) both parts
11. 11.⚠️ Is it safe to touch a fallen wire? (a) not safe (b) safe
12. 12.🔋 What should you do with used-up cells? (a) bury them in soil (b) throw them in a fire (c) give them for recycling (d) cut them open
13. 13.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a graphite rod. Does the bulb glow? (a) Yes (b) No
14. 14.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
15. 15.Which of these is true of a parallel circuit? (a) one bulb out, all go out (b) bulbs share the voltage (c) a break stops every bulb (d) each gets the full volts
16. 16.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
17. 17.🧩 Which component senses how bright it is? (a) LDR (b) LED (c) potentiometer (d) capacitor
18. 18.True or false: a mixer grinder mainly makes sound. (a) True (b) False
19. 19.🔺 A current of 20 mA flows through a 400 Ω resistor. What is the voltage across it (in volts)? =
20. 20.📏 How many milliamperes (mA) make 1 ampere? (a) 60 (b) 100 (c) 10 (d) 1000
21. 21.🤖 if (distance < 10) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 17 cm. What happens? (a) buzzer beeps (b) buzzer is silent
22. 22.What does an LDR do? (a) senses how bright it is (b) makes a beeping sound (c) beeps for an alarm (d) glows using little power
23. 23.🔍 Which is the odd one out? (a) a paper strip (b) an iron nail (c) a glass marble (d) a woollen thread
24. 24.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) cell (b) LED (c) resistor (d) battery
25. 25.What does the cloud server do? (a) carries the data (b) acts on a command (c) reads values, decides (d) stores data online
26. 26.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = V + I (d) P = I ÷ V
27. 27.True or false: “bulbs share the voltage” is true of a series circuit. (a) False (b) True
28. 28.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is ON, B is OFF and C is ON. Does the bulb glow? (a) Yes (b) No
29. 29.🔁 x = 3
    repeat 2 times { x = x × 2 }
    What is x at the end?
30. 30.🧾 A 250 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
31. 31.📶 Digital or analog: a door: open or shut? (a) digital (b) analog
32. 32.🧮 Two equal 330 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
33. 33.True or false: on an LED, the longer leg is the cathode (−). (a) False (b) True
34. 34.True or false: to build with an adult near is not safe. (a) True (b) False
35. 35.🔁 total = 0
    for i = 1 to 9 { total = total + i }
    What is total at the end?
36. 36.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a slide switch (c) a push button (d) a reed switch
37. 37.🤖 How does a new program get onto a microcontroller board? (a) typed on the chip (b) uploaded over USB (c) sent by sound (d) drawn with a pen
38. 38.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) type it all in (b) share it with friends (c) post it online (d) ask a parent first
39. 39.What does a capacitor do? (a) makes a beeping sound (b) stores a little charge (c) lets current go one way (d) has coloured bands
40. 40.🌈 In the resistor colour code, which number does brown stand for?

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