Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 62 · 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.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
2. 2.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
3. 3.🗺️ In an input → process → output plan, is “an LED lights up” the input, the process or the output? (a) output (b) process (c) input
4. 4.🔁 count = 5
   while (count < 11) { count = count + 2 }
   How many times does the loop run?
5. 5.📏 Which unit measures the push of a cell? (a) ohm (Ω) (b) volt (V) (c) ampere (A) (d) watt (W)
6. 6.Which of these is not safe? (a) fly kites in open fields (b) dry your hands first (c) open a phone charger (d) build with an adult near
7. 7.Which job needs a rain sensor? (a) open blinds at sunrise (b) start a fan when hot (c) close a window in rain (d) measure classroom noise
8. 8.🤖 Does a microwave oven usually have a microcontroller inside? (a) Yes (b) No
9. 9.🔁 What does a variable do in a program? (a) blinks an LED (b) stores a value (c) joins two wires (d) measures light
10. 10.⏱️ repeat 4 times { buzzer ON; wait 600 ms; buzzer OFF; wait 400 ms }
    How many milliseconds does this take in all?
11. 11.🔘 Which kind of switch slides side to side? (a) a push button (b) a slide switch (c) a reed switch (d) a tilt switch
12. 12.🔍 Which is the odd one out? (a) climb an electric pole (b) touch a switch when wet (c) fly a kite near wires (d) keep drinks far away
13. 13.🔺 In the V-I-R triangle, how do we find V? (a) V = I × R (b) V = I + R (c) V = R ÷ I (d) V = I ÷ R
14. 14.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
15. 15.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 5 seconds?
16. 16.🗺️ In an input → process → output plan, is “a temperature reading” the input, the process or the output? (a) process (b) input (c) output
17. 17.True or false: on an LED, the shorter leg is the anode (+). (a) False (b) True
18. 18.🧾 A family uses 180 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
19. 19.🔦 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 brass key. Does the bulb glow? (a) No (b) Yes
20. 20.⏱️ repeat 7 times { buzzer ON; wait 800 ms; buzzer OFF; wait 800 ms }
    How many milliseconds does this take in all?
21. 21.Which of these mainly makes sound? (a) a doorbell (b) a tube light (c) an exhaust fan (d) an electric drill
22. 22.🌐 A weather station sends one reading every 20 seconds. How many readings does it send in 5 minutes?
23. 23.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
24. 24.True or false: to stay away from pylons is not safe. (a) False (b) True
25. 25.Which of these is safe? (a) climb an electric pole (b) stop if a part gets hot (c) use a cable with cuts (d) open a phone charger
26. 26.True or false: to use daylight to read saves electricity. (a) True (b) False
27. 27.🧮 A 100 Ω resistor is joined in series with two equal 10 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
28. 28.🔁 repeat 4 times { repeat 6 times { beep } }
    How many beeps are there?
29. 29.Which of these is the output? (a) a soil moisture reading (b) check if temp > 30 (c) a motion sensor signal (d) an LED lights up
30. 30.True or false: a line lifted at a gap is the symbol for a switch. (a) False (b) True
31. 31.🔐 Is it a good or a risky habit to share camera links? (a) risky habit (b) good habit
32. 32.⚙️ What is an actuator? (a) a sensor (b) a program (c) an output that acts (d) a battery
33. 33.True or false: a long and a short line is the symbol for an ammeter. (a) False (b) True
34. 34.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) a display (c) a motor (d) a pump
35. 35.🔺 A current of 50 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
36. 36.💡 A red LED (it uses 2 V) is joined with a 200 Ω resistor to a 3 V supply. What current flows (in mA)?
37. 37.Which job needs a light sensor? (a) stop a robot near walls (b) switch on lamps at dusk (c) start a fan when hot (d) water a dry plant
38. 38.⚙️ Which actuator would you use to beep an alarm? (a) a pump (b) a display (c) a buzzer (d) a servo motor
39. 39.💡 What does LED stand for? (a) low energy device (b) large electric dial (c) light-emitting diode (d) light energy dial
40. 40.🌈 In the resistor colour code, which number does orange stand for?

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