Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 32 · 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.🧾 Which lamp gives the same light for the least power? (a) a candle (b) a filament bulb (c) an oil lamp (d) an LED lamp
2. 2.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) both lines (d) neither line
3. 3.⚡ A device works on 3 V and takes 0.5 A. What is its power (in watts)? =
4. 4.Which drawing is the symbol for a capacitor? (a) a line lifted at a gap (b) a circle with V inside (c) two equal parallel lines (d) triangle against a bar
5. 5.Which of these is an input? (a) a speaker (b) a turning knob (c) an LED (d) a buzzer
6. 6.Which of these means the circuit is open? (a) the switch is ON (b) a cell is taken out (c) all wires are joined (d) the loop is complete
7. 7.🔍 Which is the odd one out? (a) keep drinks far away (b) touch a fallen wire (c) dry your hands first (d) fly kites in open fields
8. 8.True or false: to stay away from pylons is not safe. (a) True (b) False
9. 9.🧾 A family uses 60 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
10. 10.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an output (c) an input (d) a fuse
11. 11.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the output (b) the process (c) the input (d) the battery
12. 12.True or false: a rubber eraser is an insulator. (a) True (b) False
13. 13.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
14. 14.⚡ Power tells us … (a) the length of a wire (b) energy used each second (c) the colour of light (d) the size of a cell
15. 15.What does a transistor do? (a) beeps for an alarm (b) has coloured bands (c) lets current go one way (d) boosts a small signal
16. 16.🔺 In the V-I-R triangle, how do we find R? (a) R = I ÷ V (b) R = V × I (c) R = V ÷ I (d) R = V + I
17. 17.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
18. 18.Which of these mainly makes sound? (a) a ceiling fan (b) a rice cooker (c) a doorbell (d) a torch
19. 19.🌐 In an IoT system, which part shows data to you? (a) phone app (b) sensor (c) microcontroller (d) actuator
20. 20.Which of these is safe? (a) take cells out after use (b) touch a switch when wet (c) fly a kite near wires (d) poke things in a socket
21. 21.📏 Which unit measures the flow of charge? (a) watt (W) (b) ampere (A) (c) volt (V) (d) ohm (Ω)
22. 22.🤖 if (temperature > 25) { fan ON } else { fan OFF }
    The temperature sensor reads 32 °C. What happens? (a) fan OFF (b) fan ON
23. 23.💡 2 identical bulbs are joined in series with a 5 V battery (ideal wires). How many volts does each bulb get? =
24. 24.📏 How many watts (W) is 3 kW?
25. 25.🏠 Which is a smart-home example? (a) a printed map (b) lights on from an app (c) a hand fan (d) a candle in a jar
26. 26.🔐 Is it a good or a risky habit to share the Wi-Fi key? (a) risky habit (b) good habit
27. 27.🧮 Adding another resistor in series makes the total resistance … (a) bigger (b) stay the same (c) smaller (d) zero
28. 28.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a rubber band. Does the bulb glow? (a) Yes (b) No
29. 29.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
30. 30.🔁 x = 4
    repeat 3 times { x = x × 2 }
    What is x at the end?
31. 31.Which drawing is the symbol for an LED? (a) triangle against a bar (b) triangle, bar and arrows (c) many long-short pairs (d) two equal parallel lines
32. 32.🔁 count = 0
    while (count < 40) { count = count + 5 }
    How many times does the loop run?
33. 33.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) battery (b) motor (c) junction (d) ammeter
34. 34.✏️ Why do engineers draw circuits with symbols? (a) to hide the circuit (b) symbols are heavier (c) to make it colourful (d) quick and clear for all
35. 35.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
36. 36.🔺 A current of 50 mA flows when 25 V is joined across a resistor. What is its resistance (in ohms)?
37. 37.🔋 6 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
38. 38.🔘 Two switches are in series. When does the bulb glow? (a) never (b) when either is ON (c) when both are OFF (d) when both are ON
39. 39.⚡ What does a traffic signal mainly change electricity into? (a) heat (b) light (c) movement (d) sound
40. 40.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a brass key across the gap. Does the bulb glow? (a) No (b) Yes

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