Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 167 · 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.⚡ A 0.3 W device works on 1.5 V. What current does it take (in amperes)? =
2. 2.🔁 x = 1
   repeat 1 time { x = x × 2 }
   What is x at the end?
3. 3.Which of these saves electricity? (a) leave the TV on standby (b) leave fridge door open (c) run fans in empty rooms (d) unplug idle chargers
4. 4.True or false: if the switch is OFF, the circuit is closed and current flows. (a) True (b) False
5. 5.What does the actuator do? (a) measures the real world (b) shows data to you (c) acts on a command (d) carries the data
6. 6.What does a thermistor do? (a) blows if current is high (b) boosts a small signal (c) senses how hot it is (d) is a resistance knob
7. 7.True or false: a push button stays where you flip it. (a) False (b) True
8. 8.🔺 In the V-I-R triangle, how do we find I? (a) I = V ÷ R (b) I = R ÷ V (c) I = V × R (d) I = V + R
9. 9.🗺️ In an input → process → output plan, is “compare with a limit” the input, the process or the output? (a) input (b) output (c) process
10. 10.🔺 A current of 25 mA flows when 12.5 V is joined across a resistor. What is its resistance (in ohms)?
11. 11.🔌 Is a brass key a conductor or an insulator? (a) a conductor (b) an insulator
12. 12.⚡ A device works on 9 V and takes 0.5 A. What is its power (in watts)? =
13. 13.What does the cloud server do? (a) stores data online (b) carries the data (c) shows data to you (d) acts on a command
14. 14.🔺 A current of 0.2 A flows when 1.6 V is joined across a resistor. What is its resistance (in ohms)?
15. 15.True or false: to log out of shared phones is a good habit. (a) False (b) True
16. 16.What does an LDR do? (a) stores a little charge (b) senses how hot it is (c) blows if current is high (d) senses how bright it is
17. 17.True or false: to stop a robot near walls, use a gas sensor. (a) False (b) True
18. 18.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) one (c) none (d) two
19. 19.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
20. 20.Which of these means the circuit is closed? (a) the switch is OFF (b) the bulb is unscrewed (c) a wire has come loose (d) the switch is ON
21. 21.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) ON (b) OFF
22. 22.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) little stars (c) dotted circles (d) wavy lines
23. 23.📶 Digital or analog: the room temperature? (a) digital (b) analog
24. 24.🔺 A 0.6 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
25. 25.🧩 Which component beeps for an alarm? (a) fuse (b) motor (c) LDR (d) buzzer
26. 26.🔌 Most metals are good … (a) insulators (b) magnets only (c) batteries (d) conductors
27. 27.True or false: “each gets the full volts” is true of a parallel circuit. (a) False (b) True
28. 28.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the if part (b) neither part (c) both parts (d) the else part
29. 29.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
30. 30.🔘 Which kind of switch springs back when let go? (a) a tilt switch (b) a push button (c) a toggle switch (d) a slide switch
31. 31.Which drawing is the symbol for a resistor? (a) one tall, one short bar (b) a small empty box (c) a circle with an X in it (d) triangle against a bar
32. 32.🔺 In the V-I-R triangle, how do we find R? (a) R = V + I (b) R = I ÷ V (c) R = V ÷ I (d) R = V × I
33. 33.🔐 Is it a good or a risky habit to keep factory passwords? (a) risky habit (b) good habit
34. 34.⏱️ A program says “wait 1500 ms”. How many seconds is that? =
35. 35.🤖 “if (A AND B)” is true when … (a) only A is true (b) both A and B are true (c) only B is true (d) both are false
36. 36.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
37. 37.Which of these is the output? (a) a button press (b) count button presses (c) an alert on the phone (d) a light level reading
38. 38.True or false: to switch off empty rooms wastes electricity. (a) True (b) False
39. 39.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) resistor (b) cell (c) ammeter (d) voltmeter
40. 40.🔁 repeat 2 times { repeat 5 times { beep } }
    How many beeps are there?

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