Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 339 · 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.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 530 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
2. 2.⚙️ What is an actuator? (a) a battery (b) a program (c) a sensor (d) an output that acts
3. 3.True or false: a thermistor smooths a wobbly supply. (a) False (b) True
4. 4.True or false: “each gets the full volts” is true of a parallel circuit. (a) False (b) True
5. 5.🧮 A 1.5 V battery is joined to 3 Ω and 12 Ω resistors in series. What current flows (in amperes)? =
6. 6.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) True (b) False
7. 7.True or false: on a cell, “usually the black wire” means the + (positive) end. (a) False (b) True
8. 8.🧮 A 470 Ω resistor is joined in series with two equal 330 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
9. 9.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) when either is ON (b) never (c) only when both are ON (d) only when both are OFF
10. 10.Which job is done by the pins? (a) shows the board is on (b) connect sensors and LEDs (c) brings power and code (d) restarts the program
11. 11.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a plastic straw across the gap. Does the bulb glow? (a) Yes (b) No
12. 12.🔋 2 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
13. 13.🔘 Which kind of switch closes near a magnet? (a) a tilt switch (b) a toggle switch (c) a slide switch (d) a reed switch
14. 14.🔍 Which is the odd one out? (a) a school bell (b) a siren (c) a loudspeaker (d) a mixer grinder
15. 15.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 37 °C. What is shown? (a) Warm (b) Cool (c) Hot
16. 16.⚡ Which tiny particles drift along a metal wire to carry the current? (a) photons (b) dust particles (c) electrons (d) water drops
17. 17.⚡ Power tells us … (a) the size of a cell (b) the colour of light (c) energy used each second (d) the length of a wire
18. 18.Which job needs a display? (a) beep an alarm (b) show a status light (c) show the temperature (d) turn to an exact angle
19. 19.🤖 Which is a safe power source for a beginner microcontroller board? (a) a wall socket directly (b) bare mains wires (c) a 230 V cable (d) USB or a 9 V battery
20. 20.🔁 x = 5
    repeat 3 times { x = x × 2 }
    What is x at the end?
21. 21.True or false: “bulbs share the voltage” is true of a series circuit. (a) True (b) False
22. 22.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 26) { show “Warm” } else { show “Cool” }
    The temperature is 42 °C. What is shown? (a) Cool (b) Hot (c) Warm
23. 23.💡 What happens if an LED is put in backwards? (a) it lights brighter (b) it makes a sound (c) it does not light (d) it changes colour
24. 24.What does a thermistor do? (a) senses how bright it is (b) limits the current (c) blows if current is high (d) senses how hot it is
25. 25.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) one (c) two (d) none
26. 26.Which of these is an IoT device? (a) a wind-up clock (b) a plain wall switch (c) a pencil sharpener (d) a fitness band with app
27. 27.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
28. 28.📶 Digital or analog: how loud a sound is? (a) analog (b) digital
29. 29.Which of these uses electricity? (a) a television (b) a wind turbine (c) a battery (d) a power station
30. 30.Which job needs a soil moisture sensor? (a) switch on lamps at dusk (b) water a dry plant (c) keep an incubator warm (d) warn of a gas leak
31. 31.💡 5 identical bulbs are in parallel and each one takes 1 A. What total current (in amperes) comes from the battery? =
32. 32.True or false: a tilt switch closes when tipped over. (a) True (b) False
33. 33.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark an 8800 Ω resistor? (a) grey-grey-orange (b) grey-grey-red (c) grey-grey-brown (d) grey-white-red
34. 34.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
35. 35.⚡ What do we call a flow of electric charge through a wire? (a) friction (b) electric current (c) sound (d) a magnet
36. 36.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
37. 37.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
38. 38.Which of these is a risky habit? (a) set up with a parent (b) install software updates (c) post your live location (d) turn off unused gadgets
39. 39.⚠️ Is it safe to fly kites in open fields? (a) safe (b) not safe
40. 40.Which of these mainly gives out light? (a) a doorbell (b) a buzzer (c) an LED lamp (d) a toaster

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids