Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 947 · 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 resistor has the colour bands yellow, black, orange. What is its value in kilo-ohms (kΩ)? =
2. 2.🔺 A 15 V supply is joined across a 300 Ω resistor. What current flows (in milliamperes, mA)?
3. 3.Which of these means the circuit is closed? (a) a wire has come loose (b) the switch is OFF (c) a wire is cut (d) the switch is ON
4. 4.🔘 A bulb and a cell are joined through 4 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
5. 5.💡 A battery lights 4 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
6. 6.Which of these gives us electricity? (a) an air conditioner (b) a television (c) a computer (d) a bicycle dynamo
7. 7.True or false: on a cell, “the flat end” means the + (positive) end. (a) True (b) False
8. 8.🔁 What must there be for a current to flow? (a) a plastic gap (b) a complete loop (c) a broken path (d) one loose end
9. 9.Which of these mainly gives out heat? (a) a table fan (b) an exhaust fan (c) a rice cooker (d) an electric drill
10. 10.🧭 Which part of a microcontroller board shows the board is on? (a) the reset button (b) the pins (c) the power LED (d) the voltage regulator
11. 11.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
12. 12.🔍 Which is the odd one out? (a) take cells out after use (b) use a cable with cuts (c) keep drinks far away (d) stop if a part gets hot
13. 13.True or false: “each gets the full volts” is true of a series circuit. (a) False (b) True
14. 14.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) only one (c) it does not matter (d) none
15. 15.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) + (positive) (b) − (negative)
16. 16.🌈 A resistor has the colour bands green, green, red. What is its value in kilo-ohms (kΩ)? =
17. 17.🔺 A current of 25 mA flows through a 500 Ω resistor. What is the voltage across it (in volts)? =
18. 18.Which job needs a motor? (a) spin a robot’s wheels (b) turn to an exact angle (c) beep an alarm (d) show the temperature
19. 19.True or false: to throw cells in a fire is not safe. (a) False (b) True
20. 20.True or false: a microcontroller needs much more power. (a) True (b) False
21. 21.Which of these mainly gives out light? (a) a street light (b) an electric kettle (c) a water heater (d) an electric iron
22. 22.True or false: “count button presses” is the process. (a) True (b) False
23. 23.🔺 A current of 2.5 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
24. 24.🌈 A resistor has the colour bands red, brown, orange. What is its value (in ohms)?
25. 25.🔁 repeat 3 times { repeat 5 times { beep } }
    How many beeps are there?
26. 26.🔌 Is a rubber eraser a conductor or an insulator? (a) an insulator (b) a conductor
27. 27.🔘 A bulb and a cell are joined through 3 switches on 3 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
28. 28.⏱️ loop forever { LED ON; wait 650 ms; LED OFF; wait 150 ms }
    How many milliseconds does one blink (ON + OFF) take?
29. 29.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 2 hours?
30. 30.🔘 Which kind of switch springs back when let go? (a) a slide switch (b) a push button (c) a toggle switch (d) a tilt switch
31. 31.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a resistor (c) a diode (d) a capacitor
32. 32.🔢 To run one loop of a plant-watering program, which is the LAST step? (a) read the soil sensor (b) wait a few seconds (c) switch the pump on/off (d) compare with the limit
33. 33.💡 3 identical bulbs are joined in series with a 6 V battery (ideal wires). How many volts does each bulb get? =
34. 34.📏 Voltmeter or ammeter: which one is joined in series? (a) voltmeter (b) ammeter
35. 35.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is ON, B is OFF and C is ON. Does the bulb glow? (a) No (b) Yes
36. 36.💡 In a series circuit, how many paths does the current have? (a) none (b) one for each bulb (c) two (d) one
37. 37.Which of these mainly makes sound? (a) an exhaust fan (b) a buzzer (c) an electric kettle (d) a tube light
38. 38.🧮 Three equal 30 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
39. 39.🧩 Which component smooths a wobbly supply? (a) buzzer (b) capacitor (c) LED (d) transistor
40. 40.💡 4 identical bulbs are joined in series with a 16 V battery (ideal wires). How many volts does each bulb get? =

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