Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 200 · 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.💡 5 identical bulbs are joined in series with a 5 V battery (ideal wires). How many volts does each bulb get? =
2. 2.🧾 A family uses 50 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
3. 3.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) the if part (c) the else part (d) both parts
4. 4.What does a reed switch do? (a) closes near a magnet (b) springs back when let go (c) stays where you flip it (d) works only while pressed
5. 5.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a plastic ruler. Does the bulb glow? (a) Yes (b) No
6. 6.True or false: “a knob turned part way” is a digital signal. (a) True (b) False
7. 7.🔌 Most metals are good … (a) magnets only (b) batteries (c) conductors (d) insulators
8. 8.Which of these is measured in watts (W)? (a) the push of a cell (b) energy used each second (c) the flow of charge (d) how much a part resists
9. 9.🔍 Which is the odd one out? (a) a steel coin (b) a glass marble (c) an iron nail (d) aluminium foil
10. 10.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 77 Ω resistor? (a) grey-violet-black (b) violet-violet-brown (c) violet-violet-black (d) violet-grey-black
11. 11.🔌 Is a water pump an input or an output for a microcontroller? (a) output (b) input
12. 12.🔁 x = 3
    repeat 1 time { x = x × 2 }
    What is x at the end?
13. 13.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 100 (d) 1000
14. 14.Which of these wastes electricity? (a) leave fridge door open (b) switch off empty rooms (c) use LED lamps (d) unplug idle chargers
15. 15.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) turns the LED off (c) blinks 500 times (d) pauses for half a second
16. 16.🤖 “if (A AND B)” is true when … (a) both are false (b) only A is true (c) both A and B are true (d) only B is true
17. 17.⚠️ Why must we never touch switches with wet hands? (a) water makes it cold (b) it is just untidy (c) it spoils the paint (d) water carries current
18. 18.Which of these mainly gives out light? (a) an electric iron (b) a night lamp (c) a water heater (d) a mixer grinder
19. 19.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
20. 20.True or false: a digital thermometer usually has a microcontroller inside. (a) True (b) False
21. 21.True or false: two equal parallel lines is the symbol for an ammeter. (a) True (b) False
22. 22.⚙️ Which actuator would you use to show the temperature? (a) an LED (b) a display (c) a motor (d) a servo motor
23. 23.💡 5 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. Does bulb 5 glow? (a) No (b) Yes
24. 24.Which of these is a risky habit? (a) read app permissions (b) share the Wi-Fi key (c) turn off unused gadgets (d) share only needed data
25. 25.Which of these mainly makes movement? (a) a mixer grinder (b) a rice cooker (c) a loudspeaker (d) a toaster
26. 26.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) none (c) two (d) one
27. 27.🔐 Is it a good or a risky habit to install software updates? (a) risky habit (b) good habit
28. 28.🔋 7 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
29. 29.⏱️ A program says “wait 4750 ms”. How many seconds is that? =
30. 30.True or false: a cotton thread is an insulator. (a) True (b) False
31. 31.💡 2 identical bulbs are joined in series with an 8 V battery (ideal wires). How many volts does each bulb get? =
32. 32.Which of these is an insulator? (a) a metal paper clip (b) aluminium foil (c) a paper strip (d) a copper wire
33. 33.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a servo motor (c) a motor (d) an LED
34. 34.⏱️ How many milliseconds is a wait of 3.5 seconds?
35. 35.Which of these is an input? (a) a small display (b) an LED (c) a speaker (d) a motion sensor
36. 36.Which of these is the input? (a) a soil moisture reading (b) check if temp > 30 (c) the pump turns on (d) count button presses
37. 37.🔁 What does “count = count + 1” do? (a) adds 1 to count (b) takes 1 away (c) sets count to 1 (d) prints 1
38. 38.⏱️ loop forever { LED ON; wait 1000 ms; LED OFF; wait 900 ms }
    How many milliseconds does one blink (ON + OFF) take?
39. 39.🌈 In the resistor colour code, which number does brown stand for?
40. 40.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the output (b) the battery (c) the input (d) the process

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