Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 537 · 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: to dry your hands first is safe. (a) True (b) False
2. 2.Which of these is not an IoT device? (a) a wind-up clock (b) a smart energy meter (c) a Wi-Fi smart plug (d) an app-controlled bulb
3. 3.🔍 Which is the odd one out? (a) a glass marble (b) a graphite rod (c) a steel coin (d) a brass key
4. 4.🗺️ In an input → process → output plan, is “an alert on the phone” the input, the process or the output? (a) process (b) input (c) output
5. 5.🧾 A 60 W filament bulb is swapped for a 9 W LED lamp that gives about the same light. Both would run for 4 hours. How many watt-hours (Wh) are saved?
6. 6.Which of these means the circuit is closed? (a) a wire has come loose (b) a wire is cut (c) all wires are joined (d) the switch is OFF
7. 7.🔁 repeat 3 times { repeat 5 times { beep } }
   How many beeps are there?
8. 8.Which drawing is the symbol for a cell? (a) a circle with a cross (b) a dot where wires meet (c) one tall, one short bar (d) triangle, bar and arrows
9. 9.🔍 A distance sensor sends a sound pulse and hears the echo 1 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
10. 10.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
11. 11.🔺 A 4.5 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
12. 12.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) pauses for half a second (c) waits 500 seconds (d) turns the LED off
13. 13.🌈 A resistor has the colour bands grey, orange, red. What is its value (in ohms)?
14. 14.🔺 A current of 25 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
15. 15.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
16. 16.🤖 Microcontroller or laptop: which one runs many apps at once? (a) laptop (b) microcontroller
17. 17.True or false: a hand pump usually has a microcontroller inside. (a) True (b) False
18. 18.Which of these is measured in watts (W)? (a) resistance (b) current (c) power (d) the push of a cell
19. 19.🔘 A bulb and a cell are joined through 4 switches on 4 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
20. 20.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a ceramic cup across the gap. Does the bulb glow? (a) No (b) Yes
21. 21.True or false: a long and a short line is the symbol for a cell. (a) False (b) True
22. 22.Which drawing is the symbol for a motor? (a) a circle with A inside (b) two equal parallel lines (c) a circle with M inside (d) triangle against a bar
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.💡 3 identical bulbs are joined in parallel across a 6 V battery (ideal wires). How many volts does each bulb get? =
25. 25.True or false: “a break stops every bulb” is true of a series circuit. (a) False (b) True
26. 26.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 5 % (c) 50 % (d) 25 %
27. 27.True or false: to keep drinks far away is not safe. (a) True (b) False
28. 28.Which of these uses electricity? (a) a cell (b) a wind turbine (c) a power station (d) a washing machine
29. 29.💡 3 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
30. 30.🔘 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 ON, B is OFF and C is OFF. Does the bulb glow? (a) Yes (b) No
31. 31.🔁 count = 2
    repeat 2 times { count = count + 7 }
    What is count at the end?
32. 32.What does the Wi-Fi link do? (a) shows data to you (b) reads values, decides (c) acts on a command (d) carries the data
33. 33.⏱️ loop forever { LED ON; wait 500 ms; LED OFF; wait 200 ms }
    How many milliseconds does one blink (ON + OFF) take?
34. 34.🔋 A 6 V battery and four 1.5 V cells are joined in series, all facing the same way. What is the total voltage (in volts)? =
35. 35.🤖 if (temperature > 25) { fan ON } else { fan OFF }
    The temperature sensor reads 27 °C. What happens? (a) fan OFF (b) fan ON
36. 36.🔋 Does a refrigerator give electricity or use electricity? (a) gives electricity (b) uses electricity
37. 37.🔺 A current of 0.2 A flows when 0.6 V is joined across a resistor. What is its resistance (in ohms)?
38. 38.🔺 A current of 1.5 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
39. 39.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
40. 40.📶 Digital or analog: many values in a range? (a) digital (b) analog

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