Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 696 · 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 weather station sends one reading every 60 seconds. How many readings does it send in 2 minutes?
2. 2.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
3. 3.Which of these means the circuit is open? (a) the switch is ON (b) a wire is cut (c) all wires are joined (d) the loop is complete
4. 4.✏️ In a circuit diagram, which part is drawn as a plain rectangle? (a) diode (b) junction (c) resistor (d) wire
5. 5.⏱️ A program says “wait 4500 ms”. How many seconds is that? =
6. 6.True or false: to leave the TV on standby wastes electricity. (a) False (b) True
7. 7.True or false: to fly kites in open fields is safe. (a) False (b) True
8. 8.📏 How many amperes (A) is 2900 mA? =
9. 9.🔺 A current of 2 A flows when 20 V is joined across a resistor. What is its resistance (in ohms)?
10. 10.True or false: current is measured in amperes (A). (a) False (b) True
11. 11.🤖 if (light < 200) { lamp ON } else { lamp OFF }
    The light sensor reads 271. What happens? (a) lamp OFF (b) lamp ON
12. 12.💡 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?
13. 13.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) capacitor (b) diode (c) bulb (d) motor
14. 14.Which of these is not safe? (a) fly kites in open fields (b) keep drinks far away (c) stop if a part gets hot (d) throw cells in a fire
15. 15.Which of these is safe? (a) keep drinks far away (b) poke things in a socket (c) use a cable with cuts (d) throw cells in a fire
16. 16.🗺️ In an input → process → output plan, is “the fan starts” the input, the process or the output? (a) output (b) process (c) input
17. 17.🔺 A current of 0.2 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
18. 18.🔍 Which is the odd one out? (a) a turning knob (b) a water pump (c) a sound sensor (d) a motion sensor
19. 19.💡 Why is house wiring done in parallel? (a) to make bulbs dim (b) so all go off together (c) each gets full voltage (d) to save copper only
20. 20.True or false: “each gets the full volts” is true of a series circuit. (a) True (b) False
21. 21.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) nothing at all (d) the final price
22. 22.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) ON (b) OFF
23. 23.True or false: a potentiometer is a resistance knob. (a) False (b) True
24. 24.🔋 Does a wind turbine give electricity or use electricity? (a) gives electricity (b) uses electricity
25. 25.Which of these is not safe? (a) touch a switch when wet (b) take cells out after use (c) dry your hands first (d) stop if a part gets hot
26. 26.🧾 A family uses 130 units of electricity in a month and each unit costs ₹6. What is the bill (in ₹)?
27. 27.✏️ In a circuit diagram, which part is drawn as one tall, one short bar? (a) bulb (b) cell (c) switch (d) voltmeter
28. 28.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 19) { show “Warm” } else { show “Cool” }
    The temperature is 22 °C. What is shown? (a) Cool (b) Hot (c) Warm
29. 29.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
30. 30.What does a fuse do? (a) boosts a small signal (b) limits the current (c) blows if current is high (d) glows using little power
31. 31.True or false: to open a phone charger is not safe. (a) False (b) True
32. 32.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
33. 33.🔦 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 safety pin. Does the bulb glow? (a) No (b) Yes
34. 34.💡 A blue LED uses 3 V and should get 10 mA. It runs from a 6 V supply. What resistor (in ohms) is needed in series?
35. 35.⏱️ loop forever { LED ON; wait 1600 ms; LED OFF; wait 400 ms }
    How many times does the LED blink in 16 seconds?
36. 36.⚡ A bicycle dynamo changes which kind of energy into electricity? (a) sound energy (b) movement energy (c) chemical energy (d) light energy
37. 37.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a copper wire across the gap. Does the bulb glow? (a) No (b) Yes
38. 38.🤖 if (temperature > 30) { fan ON } else { fan OFF }
    The temperature sensor reads 37 °C. What happens? (a) fan OFF (b) fan ON
39. 39.🌈 A gold fourth band on a resistor means the value may be off by … (a) 5 % (b) 25 % (c) 0 % (d) 50 %
40. 40.🔢 To plan an electronics project, which comes first: “build it with an adult” or “list inputs and outputs”? (a) list inputs and outputs (b) build it with an adult

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