Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 212 · 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.🔌 Most metals are good … (a) batteries (b) insulators (c) conductors (d) magnets only
2. 2.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they keep glowing (b) they get dimmer (c) they explode (d) they all go out
3. 3.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a temperature sensor (c) a sound sensor (d) a distance sensor
4. 4.🔍 Which is the odd one out? (a) use mains for a project (b) keep drinks far away (c) build with an adult near (d) take cells out after use
5. 5.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 3.5 V supply. What current flows (in mA)?
6. 6.⚡ An 18 W device works on 9 V. What current does it take (in amperes)? =
7. 7.🌐 Is a fitness band with app an IoT device? (a) not an IoT device (b) an IoT device
8. 8.Which of these is a good habit? (a) accept every permission (b) install software updates (c) share the Wi-Fi key (d) post your live location
9. 9.⚡ A 0.6 W device works on 6 V. What current does it take (in amperes)? =
10. 10.True or false: to throw cells in a fire is safe. (a) True (b) False
11. 11.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) dotted circles (c) wavy lines (d) straight lines
12. 12.💡 A red LED (it uses 2 V) is joined with a 200 Ω resistor to a 3 V supply. What current flows (in mA)?
13. 13.True or false: to leave the TV on standby saves electricity. (a) True (b) False
14. 14.🔘 Which kind of switch stays where you flip it? (a) a tilt switch (b) a push button (c) a reed switch (d) a toggle switch
15. 15.⚠️ Is it safe to touch a switch when wet? (a) not safe (b) safe
16. 16.⚠️ Is it safe to build with an adult near? (a) not safe (b) safe
17. 17.🔘 Which kind of switch closes near a magnet? (a) a tilt switch (b) a push button (c) a reed switch (d) a toggle switch
18. 18.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is ON and C is OFF. Does the bulb glow? (a) No (b) Yes
19. 19.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) junction (b) diode (c) capacitor (d) cell
20. 20.📶 On a 5 V board, a pin set HIGH gives about … (a) 50 V (b) 5 V (c) 230 V (d) 0 V
21. 21.💡 An LED is joined to a 5 V battery with no resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) may burn out (b) lights up (c) does not light
22. 22.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 200 ms }
    How many times does the LED blink in 1 second?
23. 23.True or false: resistance is measured in amperes (A). (a) True (b) False
24. 24.🔘 A bulb and a cell are joined through 3 switches on 3 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?
25. 25.Which of these means the circuit is closed? (a) a wire has come loose (b) the bulb is unscrewed (c) the switch is ON (d) a cell is taken out
26. 26.🔁 count = 2
    repeat 9 times { count = count + 5 }
    What is count at the end?
27. 27.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in parallel (b) not joined (c) by Wi-Fi (d) in series
28. 28.True or false: power is measured in watts (W). (a) True (b) False
29. 29.🤖 if (moisture < 40) { pump ON } else { pump OFF }
    The soil moisture sensor reads 53 %. What happens? (a) pump OFF (b) pump ON
30. 30.🔺 A 3 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
31. 31.⚡ A device works on 5 V and takes 0.1 A. What is its power (in watts)? =
32. 32.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) the shorter line (c) the longer line (d) neither line
33. 33.📏 Voltmeter or ammeter: which one measures voltage? (a) voltmeter (b) ammeter
34. 34.Which of these is measured in amperes (A)? (a) the flow of charge (b) how much a part resists (c) the push of a cell (d) energy used each second
35. 35.True or false: a digital alarm clock has no microcontroller inside. (a) True (b) False
36. 36.Which drawing is the symbol for a voltmeter? (a) two equal parallel lines (b) many long-short pairs (c) triangle against a bar (d) a circle with V inside
37. 37.🤖 if (temperature > 31) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 38 °C. What is shown? (a) Hot (b) Cool (c) Warm
38. 38.🔋 6 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)? =
39. 39.Which of these uses electricity? (a) a wind turbine (b) a refrigerator (c) a battery (d) a power station
40. 40.🔢 To get a sensor reading onto a phone, what comes right after “it is sent by Wi-Fi”? (a) the board reads it (b) the app shows it (c) the cloud stores it (d) the sensor measures

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