Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 189 · 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.Which of these is an input? (a) a small display (b) a motor (c) a servo motor (d) a light sensor
2. 2.🗺️ Before building a project, what should you write down first? (a) nothing at all (b) inputs and outputs (c) the box colour (d) the final price
3. 3.True or false: a toggle switch flips up or down. (a) True (b) False
4. 4.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
5. 5.💡 3 identical bulbs are joined in series with a 9 V battery (ideal wires). How many volts does each bulb get? =
6. 6.Which of these is the input? (a) a button press (b) an LED lights up (c) the fan starts (d) count button presses
7. 7.🔋 Cells joined + to − in a row (series) give … (a) the same voltage (b) no voltage (c) a smaller voltage (d) a bigger voltage
8. 8.🔺 A current of 50 mA flows through a 470 Ω resistor. What is the voltage across it (in volts)? =
9. 9.🔘 Which kind of switch stays where you flip it? (a) a tilt switch (b) a push button (c) a toggle switch (d) a slide switch
10. 10.🧩 Which component has coloured bands? (a) buzzer (b) motor (c) transistor (d) resistor
11. 11.🌐 In an IoT system, which part reads values, decides? (a) cloud server (b) actuator (c) Wi-Fi (d) microcontroller
12. 12.🧮 A 5 V battery is joined to 12 Ω and 8 Ω resistors in series. What current flows (in amperes)? =
13. 13.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 volt (c) 1 ampere (d) 1 kilowatt-hour (kWh)
14. 14.🔍 Which is the odd one out? (a) a mixer grinder (b) a buzzer (c) a loudspeaker (d) a doorbell
15. 15.🔺 A current of 1.5 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
16. 16.⏱️ How many milliseconds are in 1 second? (a) 1000 (b) 10 (c) 60 (d) 100
17. 17.🔢 To plan an electronics project, which is the FIRST step? (a) test it and fix it (b) draw the circuit diagram (c) list inputs and outputs (d) pick a problem to solve
18. 18.⏱️ A program says “wait 6250 ms”. How many seconds is that? =
19. 19.Which job needs a motor? (a) turn to an exact angle (b) move water to plants (c) spin a robot’s wheels (d) open a gate to 90°
20. 20.Which of these is a good habit? (a) accept every permission (b) keep factory passwords (c) reuse one password (d) change default passwords
21. 21.💡 In a series circuit, how many paths does the current have? (a) none (b) one (c) one for each bulb (d) two
22. 22.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a motor (c) a pump (d) a display
23. 23.🔢 To run one loop of a plant-watering program, what comes right after “switch the pump on/off”? (a) compare with the limit (b) read the soil sensor (c) wait a few seconds
24. 24.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V × I (c) P = V ÷ I (d) P = V + I
25. 25.🔋 What should you do with used-up cells? (a) give them for recycling (b) throw them in a fire (c) cut them open (d) bury them in soil
26. 26.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) True (b) False
27. 27.🤖 Does a smart watch usually have a microcontroller inside? (a) Yes (b) No
28. 28.True or false: a straight line is the symbol for a wire. (a) False (b) True
29. 29.True or false: triangle, bar and arrows is the symbol for an LED. (a) True (b) False
30. 30.Which of these is a risky habit? (a) turn off unused gadgets (b) log out of shared phones (c) change default passwords (d) share the Wi-Fi key
31. 31.🌐 Each reading a sensor sends is 25 bytes. How many bytes do 80 readings take?
32. 32.🔁 count = 3
    while (count < 18) { count = count + 5 }
    How many times does the loop run?
33. 33.🔍 Which is the odd one out? (a) the pump turns on (b) decide if soil is dry (c) a buzzer beeps (d) the fan starts
34. 34.Which drawing is the symbol for a cell? (a) a long and a short line (b) many long-short pairs (c) a circle with a cross (d) a line lifted at a gap
35. 35.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
36. 36.True or false: resistance is measured in ohms (Ω). (a) True (b) False
37. 37.True or false: “a light level reading” is the process. (a) True (b) False
38. 38.Which of these is the output? (a) a soil moisture reading (b) decide if soil is dry (c) a light level reading (d) the pump turns on
39. 39.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 22 cm. What happens? (a) buzzer beeps (b) buzzer is silent
40. 40.🔍 Which is the odd one out? (a) use LED lamps (b) use daylight to read (c) close the fridge quickly (d) leave the TV on standby

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