Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 384 · 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 circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
2. 2.🤖 Does a digital alarm clock usually have a microcontroller inside? (a) No (b) Yes
3. 3.🔋 3 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
4. 4.💡 A battery lights 2 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
5. 5.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is ON and B is OFF. Does the bulb glow? (a) No (b) Yes
6. 6.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
7. 7.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = I ÷ V (d) P = V + I
8. 8.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 19) { show “Warm” } else { show “Cool” }
   The temperature is 14 °C. What is shown? (a) Cool (b) Hot (c) Warm
9. 9.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
10. 10.🔍 A distance sensor sends a sound pulse and hears the echo 2 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
11. 11.True or false: a thermistor senses how bright it is. (a) True (b) False
12. 12.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) switch (b) wire (c) battery (d) bulb
13. 13.📏 How many milliamperes (mA) is 2.84 A?
14. 14.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
    How many milliseconds does one blink (ON + OFF) take?
15. 15.🔁 total = 0
    for i = 1 to 7 { total = total + i }
    What is total at the end?
16. 16.🔺 A current of 20 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
17. 17.🌈 A resistor has the colour bands grey, blue, black. What is its value (in ohms)?
18. 18.Which of these is a good habit? (a) change default passwords (b) share the Wi-Fi key (c) post your live location (d) accept every permission
19. 19.Which of these is measured in watts (W)? (a) voltage (b) current (c) energy used each second (d) how much a part resists
20. 20.🤖 When the main loop of a microcontroller program ends, what happens? (a) it starts again (b) it deletes itself (c) it stops forever (d) the board breaks
21. 21.🔘 Two switches are in series. When does the bulb glow? (a) when both are ON (b) when either is ON (c) when both are OFF (d) never
22. 22.🌐 What does IoT stand for? (a) Internet of Things (b) Input of Tools (c) Inside of Toys (d) Internet of Talk
23. 23.True or false: “the pump turns on” is the process. (a) True (b) False
24. 24.True or false: to stop if a part gets hot is not safe. (a) True (b) False
25. 25.⚠️ Is it safe to keep drinks far away? (a) not safe (b) safe
26. 26.📏 How many milliamperes (mA) is 2.68 A?
27. 27.⚡ A cell changes stored chemical energy into which kind of energy? (a) nuclear energy (b) wind energy (c) electrical energy (d) sound energy
28. 28.Which of these is an insulator? (a) a metal paper clip (b) a dry cork (c) a steel coin (d) a steel spoon
29. 29.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
30. 30.Which of these means the circuit is closed? (a) the loop is complete (b) a wire has come loose (c) a cell is taken out (d) the bulb is unscrewed
31. 31.🔍 Which is the odd one out? (a) a mixer grinder (b) an exhaust fan (c) a ceiling fan (d) a water heater
32. 32.🔺 A current of 10 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
33. 33.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
34. 34.True or false: to touch a switch when wet is safe. (a) False (b) True
35. 35.🔺 A current of 10 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
36. 36.🔁 count = 3
    while (count < 43) { count = count + 5 }
    How many times does the loop run?
37. 37.🔁 count = 9
    repeat 3 times { count = count + 3 }
    What is count at the end?
38. 38.🔐 Is it a good or a risky habit to set up with a parent? (a) risky habit (b) good habit
39. 39.🤖 “if (A AND B)” is true when … (a) both are false (b) only B is true (c) both A and B are true (d) only A is true
40. 40.True or false: resistance is measured in watts (W). (a) True (b) False

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