Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 588 · 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.✏️ In a circuit diagram, which part is drawn as a straight line? (a) diode (b) wire (c) battery (d) motor
2. 2.🌈 Which band is read first on a resistor? (a) the one nearest an end (b) the widest gap (c) the gold band (d) any band
3. 3.🔁 What does a variable do in a program? (a) joins two wires (b) measures light (c) stores a value (d) blinks an LED
4. 4.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) wait a few seconds (b) compare with the limit (c) switch the pump on/off
5. 5.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) an LED (c) a motor (d) a pump
6. 6.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
   The distance sensor reads 12 cm. What happens? (a) buzzer beeps (b) buzzer is silent
7. 7.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) the longer line (c) the shorter line (d) both lines
8. 8.🔦 A circuit has a new cell, a good bulb and a switch that is OFF. All the wires are firmly joined. A gap in one wire is bridged by an iron nail. Does the bulb glow? (a) Yes (b) No
9. 9.🤖 “if (A AND B)” is true when … (a) both are false (b) both A and B are true (c) only A is true (d) only B is true
10. 10.💡 An LED is joined to a 5 V battery through a 220 Ω resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) does not light (b) lights up (c) may burn out
11. 11.True or false: to run fans in empty rooms wastes electricity. (a) False (b) True
12. 12.Which of these is safe? (a) fly a kite near wires (b) stop if a part gets hot (c) climb an electric pole (d) poke things in a socket
13. 13.🧮 Two equal 220 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
14. 14.🔁 count = 2
    repeat 6 times { count = count + 10 }
    What is count at the end?
15. 15.🔦 A circuit has a used-up (dead) 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 rubber band. Does the bulb glow? (a) Yes (b) No
16. 16.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
    The temperature is 10 °C. What is shown? (a) Hot (b) Warm (c) Cool
17. 17.Which of these is an output? (a) a buzzer (b) a keypad (c) a turning knob (d) a sound sensor
18. 18.Which of these mainly gives out heat? (a) a school bell (b) an electric toy car (c) a tube light (d) a room heater
19. 19.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) by Wi-Fi (c) in series (d) in parallel
20. 20.Which drawing is the symbol for a resistor? (a) one tall, one short bar (b) a circle with a cross (c) a small empty box (d) two or more cell symbols
21. 21.True or false: to use mains for a project is not safe. (a) True (b) False
22. 22.💡 Does it save or waste electricity to unplug idle chargers? (a) saves electricity (b) wastes electricity
23. 23.🤖 What is a microcontroller? (a) a type of battery (b) a computer on one chip (c) a big desktop computer (d) a kind of bulb
24. 24.⚡ A 2.25 W device works on 1.5 V. What current does it take (in amperes)? =
25. 25.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) battery (b) junction (c) voltmeter (d) capacitor
26. 26.🔍 Which is the odd one out? (a) climb an electric pole (b) keep drinks far away (c) use small battery cells (d) fly kites in open fields
27. 27.⚡ A device works on 6 V and takes 0.2 A. What is its power (in watts)? =
28. 28.🔗 Series or parallel circuit: “a break stops every bulb”? (a) series (b) parallel
29. 29.🧩 A capacitor in a circuit can … (a) make light (b) store charge briefly (c) spin a wheel (d) measure heat
30. 30.True or false: an electric kettle mainly gives out heat. (a) True (b) False
31. 31.🔍 Which is the odd one out? (a) a button press (b) a light level reading (c) a temperature reading (d) an LED lights up
32. 32.🔘 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 OFF, B is ON and C is OFF. Does the bulb glow? (a) No (b) Yes
33. 33.🔘 When a switch is ON, the circuit is … (a) cut (b) broken (c) open (d) closed
34. 34.Which job needs a sound sensor? (a) start a fan when hot (b) spot someone walking in (c) switch on with a clap (d) water a dry plant
35. 35.🧮 Resistors of 10 Ω, 470 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
36. 36.True or false: a street light mainly makes movement. (a) True (b) False
37. 37.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. Does the bulb glow? (a) No (b) Yes
38. 38.🔍 Which is the odd one out? (a) a buzzer (b) an electric toy car (c) an electric drill (d) a mixer grinder
39. 39.🧮 Two equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
40. 40.🧮 Adding another resistor in series makes the total resistance … (a) stay the same (b) zero (c) bigger (d) smaller

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