Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 101 · 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.⚡ What does a night lamp mainly change electricity into? (a) sound (b) light (c) heat (d) movement
2. 2.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 24) { show “Warm” } else { show “Cool” }
   The temperature is 13 °C. What is shown? (a) Hot (b) Cool (c) Warm
3. 3.Which of these gives us electricity? (a) a battery (b) an air conditioner (c) a mobile phone (d) a refrigerator
4. 4.🌐 A weather station sends one reading every 10 seconds. How many readings does it send in 4 minutes?
5. 5.💡 Does it save or waste electricity to run fans in empty rooms? (a) wastes electricity (b) saves electricity
6. 6.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) diode (b) cell (c) motor (d) LED
7. 7.🧮 Resistors of 10 Ω, 330 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
8. 8.💡 4 identical bulbs are in parallel and each one takes 0.5 A. What total current (in amperes) comes from the battery? =
9. 9.🌈 A resistor has the colour bands red, green, red. What is its value in kilo-ohms (kΩ)? =
10. 10.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 6 minutes?
11. 11.Which of these wastes electricity? (a) set the AC to 24 °C (b) close the fridge quickly (c) use old filament bulbs (d) use LED lamps
12. 12.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) True (b) False
13. 13.True or false: a toy robot usually has a microcontroller inside. (a) False (b) True
14. 14.⚡ A home appliance on the 230 V mains takes 0.5 A. What is its power (in watts)?
15. 15.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a light sensor (c) a temperature sensor (d) a gas sensor
16. 16.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
17. 17.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an input (c) a power source (d) an output
18. 18.💡 2 identical bulbs are joined in series with a 5 V battery (ideal wires). How many volts does each bulb get? =
19. 19.🤖 Microcontroller or laptop: which one has a built-in keyboard? (a) laptop (b) microcontroller
20. 20.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
21. 21.🔺 In the V-I-R triangle, how do we find I? (a) I = R ÷ V (b) I = V × R (c) I = V + R (d) I = V ÷ R
22. 22.True or false: a loudspeaker mainly gives out heat. (a) True (b) False
23. 23.🌈 In the resistor colour code, which number does blue stand for?
24. 24.True or false: a buzzer blows if current is high. (a) False (b) True
25. 25.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a cotton thread across the gap. Does the bulb glow? (a) No (b) Yes
26. 26.True or false: “a single current path” is true of a parallel circuit. (a) True (b) False
27. 27.🔋 8 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
28. 28.🔺 A 5 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
29. 29.True or false: to stop if a part gets hot is not safe. (a) False (b) True
30. 30.⚡ What does an electric drill mainly change electricity into? (a) heat (b) light (c) movement (d) sound
31. 31.🧮 A 100 Ω resistor is joined in series with two equal 40 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
32. 32.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is ON and B is OFF. Does the bulb glow? (a) Yes (b) No
33. 33.💡 5 identical bulbs are joined in parallel across a 4.5 V battery (ideal wires). How many volts does each bulb get? =
34. 34.Which of these gives us electricity? (a) a power station (b) a water pump (c) a washing machine (d) a television
35. 35.🔋 What should you do with used-up cells? (a) throw them in a fire (b) cut them open (c) bury them in soil (d) give them for recycling
36. 36.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
37. 37.🔁 count = 1
    while (count < 11) { count = count + 2 }
    How many times does the loop run?
38. 38.🤖 if (light < 200) { lamp ON } else { lamp OFF }
    The light sensor reads 267. What happens? (a) lamp ON (b) lamp OFF
39. 39.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
40. 40.🧭 Which part of a microcontroller board brings power and code? (a) the power LED (b) the USB port (c) the pins (d) the voltage regulator

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