Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 926 · 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 0.6 W device works on 3 V. What current does it take (in amperes)? =
2. 2.💡 Why is house wiring done in parallel? (a) so all go off together (b) to make bulbs dim (c) to save copper only (d) each gets full voltage
3. 3.Which job needs a distance sensor? (a) water a dry plant (b) make a parking alarm (c) open blinds at sunrise (d) spot someone walking in
4. 4.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 10 (c) 1000 (d) 100
5. 5.⚡ What does an LED lamp mainly change electricity into? (a) light (b) heat (c) sound (d) movement
6. 6.🧮 Two equal 330 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
7. 7.🔋 5 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
8. 8.True or false: an electric drill mainly gives out light. (a) False (b) True
9. 9.🤖 Where does the board keep its program when the power is off? (a) the resistor (b) the USB cable (c) flash memory (d) the power LED
10. 10.Which of these saves electricity? (a) iron one shirt at a time (b) use LED lamps (c) leave fridge door open (d) use old filament bulbs
11. 11.🔋 How many 1.5 V cells must be joined in series to give 7.5 V?
12. 12.Which drawing is the symbol for an ammeter? (a) a circle with a cross (b) a circle with A inside (c) two or more cell symbols (d) a circle with V inside
13. 13.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) mute it when not in use (d) put it in the bathroom
14. 14.🔁 x = 2
    repeat 2 times { x = x × 2 }
    What is x at the end?
15. 15.🤖 “if (A AND B)” is true when … (a) both are false (b) only B is true (c) only A is true (d) both A and B are true
16. 16.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
17. 17.🔺 A current of 0.2 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
18. 18.True or false: to take cells out after use is not safe. (a) False (b) True
19. 19.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
20. 20.🔍 Which sensor would you use to warn of a gas leak? (a) a gas sensor (b) a rain sensor (c) a motion sensor (d) a light sensor
21. 21.True or false: a push button slides side to side. (a) False (b) True
22. 22.🔋 How many 2 V cells must be joined in series to give 8 V?
23. 23.🧭 Which part of a microcontroller board shows the board is on? (a) the power LED (b) the USB port (c) the pins (d) the main chip
24. 24.⏱️ How many milliseconds is a wait of 4.4 seconds?
25. 25.🔁 What do we call a circuit with a break in it? (a) a closed circuit (b) an open circuit (c) a series circuit (d) a full circuit
26. 26.True or false: on an LED, the round-side leg is the anode (+). (a) False (b) True
27. 27.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
28. 28.🔢 To plan an electronics project, which comes first: “draw the circuit diagram” or “test it and fix it”? (a) draw the circuit diagram (b) test it and fix it
29. 29.🔍 Which is the odd one out? (a) tap unknown app links (b) set up with a parent (c) accept every permission (d) keep factory passwords
30. 30.⏱️ repeat 4 times { buzzer ON; wait 200 ms; buzzer OFF; wait 800 ms }
    How many milliseconds does this take in all?
31. 31.💡 An LED is joined to a 9 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
32. 32.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) zero (c) bigger (d) stay the same
33. 33.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 150 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
34. 34.Which of these is measured in watts (W)? (a) voltage (b) current (c) energy used each second (d) how much a part resists
35. 35.🔋 Does a mobile phone give electricity or use electricity? (a) uses electricity (b) gives electricity
36. 36.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) False (b) True
37. 37.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = V ÷ I (c) R = I ÷ V (d) R = V + I
38. 38.Which job needs a motor? (a) open a gate to 90° (b) show a status light (c) show the temperature (d) spin a robot’s wheels
39. 39.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
40. 40.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a program (d) a battery

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