Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 69 · 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.⚠️ Who should be with you when you build a circuit? (a) nobody (b) a stranger online (c) a trusted adult (d) a younger child
2. 2.True or false: a digital thermometer has no microcontroller inside. (a) False (b) True
3. 3.Which of these is a risky habit? (a) change default passwords (b) set up with a parent (c) install software updates (d) reuse one password
4. 4.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a fuse (d) a power source
5. 5.🔺 A current of 2 A flows when 12 V is joined across a resistor. What is its resistance (in ohms)?
6. 6.🔍 Which is the odd one out? (a) a doorbell (b) a buzzer (c) a loudspeaker (d) a street light
7. 7.What does a transistor do? (a) is a resistance knob (b) stores a little charge (c) boosts a small signal (d) beeps for an alarm
8. 8.Which of these has no microcontroller inside? (a) a smart watch (b) a plain wall switch (c) a microwave oven (d) a TV remote
9. 9.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
10. 10.Which of these is measured in amperes (A)? (a) voltage (b) current (c) the push of a cell (d) energy used each second
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 rubber band. Does the bulb glow? (a) No (b) Yes
12. 12.🔍 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
13. 13.Which of these uses electricity? (a) a power station (b) a battery (c) a washing machine (d) a solar panel
14. 14.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
15. 15.True or false: “one out, the rest glow” is true of a parallel circuit. (a) True (b) False
16. 16.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 4 V supply. What current flows (in mA)?
17. 17.🧾 A family uses 160 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
18. 18.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) it does not matter (c) none (d) only one
19. 19.💡 Why does an LED need a resistor in series? (a) to limit the current (b) to change its colour (c) to store charge (d) to make it brighter
20. 20.True or false: “HIGH or LOW only” is a digital signal. (a) False (b) True
21. 21.🔁 count = 3
    repeat 8 times { count = count + 4 }
    What is count at the end?
22. 22.🔌 Is a copper wire a conductor or an insulator? (a) an insulator (b) a conductor
23. 23.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = V × I (c) P = I ÷ V (d) P = V + I
24. 24.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?
25. 25.🔌 Is a steel coin a conductor or an insulator? (a) a conductor (b) an insulator
26. 26.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is OFF and B is ON. Does the bulb glow? (a) No (b) Yes
27. 27.🔦 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 an iron nail. Does the bulb glow? (a) No (b) Yes
28. 28.🔁 x = 2
    repeat 3 times { x = x × 2 }
    What is x at the end?
29. 29.🧮 A 100 Ω resistor is joined in series with two equal 100 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
30. 30.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) LED (b) voltmeter (c) capacitor (d) motor
31. 31.⚡ Power tells us … (a) the size of a cell (b) energy used each second (c) the length of a wire (d) the colour of light
32. 32.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) the final price (d) nothing at all
33. 33.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) series (b) parallel
34. 34.🔐 Why install updates on IoT devices? (a) they change the colour (b) they delete the Wi-Fi (c) they fix security holes (d) they make it heavier
35. 35.🤖 if (moisture < 30) { pump ON } else { pump OFF }
    The soil moisture sensor reads 44 %. What happens? (a) pump ON (b) pump OFF
36. 36.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 1 glow? (a) Yes (b) No
37. 37.⚡ A device works on 1.5 V and takes 1.5 A. What is its power (in watts)? =
38. 38.What does a toggle switch do? (a) stays where you flip it (b) slides side to side (c) works only while pressed (d) closes when tipped over
39. 39.🔘 When a switch is ON, the circuit is … (a) broken (b) closed (c) open (d) cut
40. 40.Which of these is a good habit? (a) accept every permission (b) ignore update messages (c) turn off unused gadgets (d) share camera links

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