Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 135 · 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.True or false: a microwave oven usually has a microcontroller inside. (a) False (b) True
2. 2.True or false: a spinning top has no microcontroller inside. (a) False (b) True
3. 3.🧮 A 20 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)?
4. 4.What does the cloud server do? (a) measures the real world (b) carries the data (c) stores data online (d) acts on a command
5. 5.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
6. 6.🔋 Does a bicycle dynamo give electricity or use electricity? (a) uses electricity (b) gives electricity
7. 7.🗺️ Before building a project, what should you write down first? (a) the final price (b) nothing at all (c) the box colour (d) inputs and outputs
8. 8.🤖 “if (A AND B)” is true when … (a) only B is true (b) only A is true (c) both A and B are true (d) both are false
9. 9.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 20 Ω resistor? (a) orange-red-black (b) red-black-brown (c) red-black-black (d) orange-black-black
10. 10.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) both lines (c) neither line (d) the shorter line
11. 11.🔦 A circuit has a new 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 woollen thread. Does the bulb glow? (a) Yes (b) No
12. 12.🔺 A 10 V supply is joined across a 20 Ω resistor. What current flows (in amperes)? =
13. 13.🗺️ In an input → process → output plan, is “compare with a limit” the input, the process or the output? (a) process (b) output (c) input
14. 14.🔺 A current of 0.1 A flows when 0.3 V is joined across a resistor. What is its resistance (in ohms)?
15. 15.🔍 Which is the odd one out? (a) a buzzer (b) a speaker (c) a sound sensor (d) a motor
16. 16.True or false: to use small battery cells is not safe. (a) False (b) True
17. 17.🔌 Is a plastic straw a conductor or an insulator? (a) an insulator (b) a conductor
18. 18.🔍 Which is the odd one out? (a) accept every permission (b) share only needed data (c) set a strong password (d) read app permissions
19. 19.🗺️ 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
20. 20.Which of these is an output? (a) a keypad (b) a motion sensor (c) a light sensor (d) a small display
21. 21.📏 Voltmeter or ammeter: which one is joined in series? (a) ammeter (b) voltmeter
22. 22.🌐 In an IoT system, which part reads values, decides? (a) Wi-Fi (b) sensor (c) microcontroller (d) phone app
23. 23.🔢 To plan an electronics project, which is the FIRST step? (a) draw the circuit diagram (b) test it and fix it (c) list inputs and outputs (d) pick a problem to solve
24. 24.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is OFF and C is ON. Does the bulb glow? (a) Yes (b) No
25. 25.💡 In a series circuit, how many paths does the current have? (a) two (b) none (c) one for each bulb (d) one
26. 26.🔘 Which kind of switch closes when tipped over? (a) a push button (b) a reed switch (c) a slide switch (d) a tilt switch
27. 27.True or false: a slide switch slides side to side. (a) False (b) True
28. 28.Which of these is true of a parallel circuit? (a) used in house wiring (b) one bulb out, all go out (c) bulbs share the voltage (d) a break stops every bulb
29. 29.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) post it online (b) ask a parent first (c) type it all in (d) share it with friends
30. 30.Which of these is true of a series circuit? (a) each gets the full volts (b) one out, the rest glow (c) a break stops every bulb (d) own switch for each bulb
31. 31.Which job needs a servo motor? (a) open a gate to 90° (b) show the temperature (c) show a status light (d) beep an alarm
32. 32.🔺 A current of 0.2 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
33. 33.🔌 Is a motor an input or an output for a microcontroller? (a) output (b) input
34. 34.🔺 A current of 25 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
35. 35.🌈 A resistor has the colour bands grey, white, black. What is its value (in ohms)?
36. 36.Which of these mainly makes movement? (a) a siren (b) a mixer grinder (c) a night lamp (d) a buzzer
37. 37.⚡ A home appliance on the 230 V mains takes 0.5 A. What is its power (in watts)?
38. 38.🔍 Which is the odd one out? (a) fly a kite near wires (b) build with an adult near (c) open a phone charger (d) touch a switch when wet
39. 39.Which of these is safe? (a) build with an adult near (b) poke things in a socket (c) touch a fallen wire (d) throw cells in a fire
40. 40.🔁 repeat 5 times { repeat 4 times { beep } }
    How many beeps are there?

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