Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 414 · 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 cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is ON and B is OFF. Does the bulb glow? (a) No (b) Yes
2. 2.💡 2 identical bulbs are in parallel and each one takes 0.2 A. What total current (in amperes) comes from the battery? =
3. 3.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
4. 4.Which of these is an insulator? (a) a copper wire (b) a plastic ruler (c) a brass key (d) aluminium foil
5. 5.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 350 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
6. 6.⚡ A 12 W device works on 6 V. What current does it take (in amperes)? =
7. 7.🔗 Series or parallel circuit: “own switch for each bulb”? (a) parallel (b) series
8. 8.🔁 What does a variable do in a program? (a) blinks an LED (b) joins two wires (c) measures light (d) stores a value
9. 9.Which of these is not safe? (a) stay away from pylons (b) take cells out after use (c) touch a switch when wet (d) use small battery cells
10. 10.⚙️ What is an actuator? (a) a battery (b) a sensor (c) a program (d) an output that acts
11. 11.Which of these is the output? (a) a buzzer beeps (b) check if temp > 30 (c) a light level reading (d) count button presses
12. 12.True or false: a safety pin is an insulator. (a) False (b) True
13. 13.Which drawing is the symbol for a bulb? (a) triangle against a bar (b) a circle with M inside (c) many long-short pairs (d) a circle with an X in it
14. 14.⏱️ loop forever { LED ON; wait 400 ms; LED OFF; wait 1000 ms }
    How many milliseconds does one blink (ON + OFF) take?
15. 15.Which of these is an input? (a) a small display (b) a servo motor (c) an LED (d) a motion sensor
16. 16.🧮 Two resistors in parallel give a total that is … (a) less than either one (b) always zero (c) more than either one (d) their sum
17. 17.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
18. 18.True or false: to change default passwords is a good habit. (a) False (b) True
19. 19.⏱️ How many milliseconds is a wait of 3 seconds?
20. 20.🔌 Is a servo motor an input or an output for a microcontroller? (a) input (b) output
21. 21.True or false: a circle with A inside is the symbol for a voltmeter. (a) False (b) True
22. 22.True or false: “one out, the rest glow” is true of a parallel circuit. (a) False (b) True
23. 23.🔺 In the V-I-R triangle, how do we find V? (a) V = I × R (b) V = I + R (c) V = R ÷ I (d) V = I ÷ R
24. 24.🔺 A 60 V supply is joined across a 20 Ω resistor. What current flows (in amperes)? =
25. 25.✏️ In a circuit diagram, which part is drawn as a plain rectangle? (a) battery (b) capacitor (c) resistor (d) bulb
26. 26.Which of these is a conductor? (a) a copper wire (b) a cotton thread (c) a rubber eraser (d) a dry cork
27. 27.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
28. 28.🔺 A current of 25 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
29. 29.🔐 Why install updates on IoT devices? (a) they make it heavier (b) they change the colour (c) they delete the Wi-Fi (d) they fix security holes
30. 30.True or false: “how bright a room is” is an analog signal. (a) True (b) False
31. 31.🔁 repeat 6 times { repeat 6 times { beep } }
    How many beeps are there?
32. 32.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
33. 33.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in parallel (c) in series (d) not joined
34. 34.Which of these is an input? (a) a turning knob (b) a buzzer (c) a water pump (d) a motor
35. 35.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 250 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
36. 36.🧮 Resistors of 47 Ω, 220 Ω and 20 Ω are joined in series. What is the total resistance (in ohms)?
37. 37.🌐 Each reading a sensor sends is 25 bytes. How many bytes do 50 readings take?
38. 38.True or false: to share only needed data is a risky habit. (a) True (b) False
39. 39.⚡ Which formula gives electric power? (a) P = V + I (b) P = V ÷ I (c) P = V × I (d) P = I ÷ V
40. 40.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) only when both are ON (b) only when both are OFF (c) when either is ON (d) never

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