Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 450 · 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.🤖 When the main loop of a microcontroller program ends, what happens? (a) it stops forever (b) it deletes itself (c) the board breaks (d) it starts again
2. 2.🔍 Which is the odd one out? (a) an exhaust fan (b) a street light (c) a torch (d) a tube light
3. 3.🧮 Resistors of 220 Ω, 22 Ω, 330 Ω and 330 Ω are joined in series. What is the total resistance (in ohms)?
4. 4.📶 A pin that reads a push button is set as … (a) a battery (b) an input (c) an output (d) a resistor
5. 5.True or false: a plain wall switch has no microcontroller inside. (a) False (b) True
6. 6.🔋 What is a battery? (a) two or more cells joined (b) one single wire (c) a switch with a lid (d) a kind of bulb
7. 7.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 50 % (c) 5 % (d) 25 %
8. 8.True or false: “each gets the full volts” is true of a parallel circuit. (a) True (b) False
9. 9.🌐 Each reading a sensor sends is 10 bytes. How many bytes do 200 readings take?
10. 10.🔌 Which metal is used for most electric wires at home? (a) plastic (b) copper (c) rubber (d) glass
11. 11.🧩 Which part changes electrical energy into movement? (a) a resistor (b) a fuse (c) an LED (d) a motor
12. 12.🔍 Which is the odd one out? (a) a traffic signal (b) a night lamp (c) an electric drill (d) an LED lamp
13. 13.🧮 Two resistors in parallel give a total that is … (a) less than either one (b) their sum (c) more than either one (d) always zero
14. 14.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) LED (b) motor (c) cell (d) capacitor
15. 15.💡 4 identical bulbs are in parallel and each one takes 0.2 A. What total current (in amperes) comes from the battery? =
16. 16.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
17. 17.⚙️ Which actuator would you use to move water to plants? (a) a servo motor (b) an LED (c) a motor (d) a pump
18. 18.True or false: the ammeter measures voltage. (a) False (b) True
19. 19.🔌 Is a graphite rod a conductor or an insulator? (a) a conductor (b) an insulator
20. 20.⚠️ Why must we never touch switches with wet hands? (a) water makes it cold (b) water carries current (c) it spoils the paint (d) it is just untidy
21. 21.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a cotton thread across the gap. Does the bulb glow? (a) No (b) Yes
22. 22.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
23. 23.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they all go out (b) they get dimmer (c) they keep glowing (d) they explode
24. 24.Which job needs a rain sensor? (a) make a parking alarm (b) water a dry plant (c) close a window in rain (d) switch on with a clap
25. 25.True or false: “a single current path” is true of a series circuit. (a) False (b) True
26. 26.🧮 A 33 Ω resistor is joined in series with two equal 10 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
27. 27.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
28. 28.🔍 Which is the odd one out? (a) turn off unused gadgets (b) set a strong password (c) tap unknown app links (d) change default passwords
29. 29.🔦 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 wooden stick. Does the bulb glow? (a) Yes (b) No
30. 30.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) in series (c) in parallel (d) by Wi-Fi
31. 31.Which of these is a conductor? (a) a ceramic cup (b) a glass marble (c) a rubber band (d) a copper wire
32. 32.💡 A red LED uses 2 V and should get 25 mA. It runs from a 6 V supply. What resistor (in ohms) is needed in series?
33. 33.⚡ What does an LED lamp mainly change electricity into? (a) light (b) movement (c) sound (d) heat
34. 34.True or false: a street light mainly gives out heat. (a) False (b) True
35. 35.🔁 count = 2
    repeat 3 times { count = count + 9 }
    What is count at the end?
36. 36.🔺 In the V-I-R triangle, how do we find R? (a) R = V + I (b) R = I ÷ V (c) R = V ÷ I (d) R = V × I
37. 37.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
38. 38.Which drawing is the symbol for a diode? (a) triangle against a bar (b) a long and a short line (c) triangle, bar and arrows (d) two equal parallel lines
39. 39.True or false: “a knob turned part way” is a digital signal. (a) True (b) False
40. 40.True or false: a rubber band is a conductor. (a) True (b) False

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