Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 64 · 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 means the circuit is open? (a) all wires are joined (b) the switch is ON (c) the loop is complete (d) a wire has come loose
2. 2.⏱️ loop forever { LED ON; wait 600 ms; LED OFF; wait 300 ms }
   How many milliseconds does one blink (ON + OFF) take?
3. 3.⚠️ Who should be with you when you build a circuit? (a) a stranger online (b) a trusted adult (c) nobody (d) a younger child
4. 4.🔐 Who should decide which smart devices go in a child’s room? (a) an online stranger (b) the app’s adverts (c) nobody at all (d) a parent or guardian
5. 5.Which of these is an IoT device? (a) a paper calendar (b) a battery torch (c) a plain table fan (d) a smart energy meter
6. 6.Which job is done by the power LED? (a) shows the board is on (b) connect sensors and LEDs (c) brings power and code (d) restarts the program
7. 7.🔍 Which is the odd one out? (a) a water heater (b) an electric kettle (c) an LED lamp (d) a toaster
8. 8.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a servo motor (c) a pump (d) a buzzer
9. 9.🔢 To run one loop of a plant-watering program, what comes right after “compare with the limit”? (a) read the soil sensor (b) wait a few seconds (c) switch the pump on/off
10. 10.💡 An LED is joined to a 9 V battery through a 470 Ω resistor; its long leg goes to the − side and its short leg to the + side. What happens? (a) may burn out (b) lights up (c) does not light
11. 11.True or false: a toggle switch flips up or down. (a) True (b) False
12. 12.🧾 A 1000 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
13. 13.Which job needs an LED? (a) show a status light (b) spin a robot’s wheels (c) show the temperature (d) move water to plants
14. 14.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) not joined (c) in parallel (d) by Wi-Fi
15. 15.🌈 A resistor has the colour bands grey, green, orange. What is its value (in ohms)?
16. 16.🔍 Which is the odd one out? (a) a smart energy meter (b) a Wi-Fi weather station (c) a plain table fan (d) a Wi-Fi smart plug
17. 17.What does a capacitor do? (a) blows if current is high (b) glows using little power (c) smooths a wobbly supply (d) makes things spin
18. 18.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) gets bigger (c) becomes zero (d) stays the same
19. 19.🔺 A current of 1.5 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
20. 20.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a ceramic cup. Does the bulb glow? (a) No (b) Yes
21. 21.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a resistor (c) a capacitor (d) a diode
22. 22.🔘 Which kind of switch stays where you flip it? (a) a slide switch (b) a reed switch (c) a push button (d) a toggle switch
23. 23.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V × I (c) P = V + I (d) P = V ÷ I
24. 24.🔋 How many 1.5 V cells must be joined in series to give 10.5 V?
25. 25.⏱️ A program says “wait 9250 ms”. How many seconds is that? =
26. 26.📶 A pin set LOW gives about … (a) 5 V (b) 0 V (c) 1.5 V (d) 9 V
27. 27.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
28. 28.🔺 A 6 V supply is joined across a 4 Ω resistor. What current flows (in amperes)? =
29. 29.🧮 A 220 Ω resistor is joined in series with two equal 1000 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
30. 30.True or false: to fly kites in open fields is safe. (a) True (b) False
31. 31.🗺️ In an input → process → output plan, is “an alert on the phone” the input, the process or the output? (a) input (b) output (c) process
32. 32.⚡ Which tiny particles drift along a metal wire to carry the current? (a) electrons (b) dust particles (c) water drops (d) photons
33. 33.True or false: “a soil moisture reading” is the process. (a) False (b) True
34. 34.True or false: a buzzer makes a beeping sound. (a) False (b) True
35. 35.⚠️ Is it safe to fly a kite near wires? (a) safe (b) not safe
36. 36.Which of these is a risky habit? (a) set a strong password (b) set up with a parent (c) ignore update messages (d) turn off unused gadgets
37. 37.🔺 A current of 1.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
38. 38.🔺 A current of 0.1 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
39. 39.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
40. 40.🤖 What is a microcontroller? (a) a kind of bulb (b) a computer on one chip (c) a big desktop computer (d) a type of battery

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