Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 265 · 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.Which of these is true of a series circuit? (a) many paths for current (b) a break stops every bulb (c) own switch for each bulb (d) one out, the rest glow
2. 2.True or false: on an LED, the shorter leg is the anode (+). (a) True (b) False
3. 3.🤖 Does a washing machine usually have a microcontroller inside? (a) No (b) Yes
4. 4.🗺️ In an input → process → output plan, is “decide if soil is dry” the input, the process or the output? (a) input (b) output (c) process
5. 5.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
6. 6.⚡ What do we call a flow of electric charge through a wire? (a) sound (b) a magnet (c) friction (d) electric current
7. 7.🧮 A 7 V battery is joined to 4 Ω and 10 Ω resistors in series. What current flows (in amperes)? =
8. 8.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) zero (c) bigger (d) stay the same
9. 9.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) False (b) True
10. 10.🌐 A soil sensor sends a reading to an app every 30 minutes. How many readings arrive in 3 hours?
11. 11.True or false: a water heater mainly gives out light. (a) True (b) False
12. 12.📶 Digital or analog: a button: pressed or not? (a) analog (b) digital
13. 13.Which of these wastes electricity? (a) unplug idle chargers (b) leave fridge door open (c) close the fridge quickly (d) switch off empty rooms
14. 14.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the switch (c) the base (d) the filament
15. 15.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave the TV on standby (c) run fans in empty rooms (d) close the fridge quickly
16. 16.🔺 A current of 10 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
17. 17.🤖 if (temperature > 33) { show “Hot” } else if (temperature > 23) { show “Warm” } else { show “Cool” }
    The temperature is 41 °C. What is shown? (a) Cool (b) Hot (c) Warm
18. 18.True or false: a digital alarm clock has no microcontroller inside. (a) True (b) False
19. 19.🗺️ 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
20. 20.🔋 How many 1.2 V cells must be joined in series to give 4.8 V?
21. 21.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = R ÷ V (c) I = V ÷ R (d) I = V × R
22. 22.⏱️ How many milliseconds is a wait of 0.1 seconds?
23. 23.True or false: a dot where wires meet is the symbol for a junction. (a) True (b) False
24. 24.🔍 Which is the odd one out? (a) a buzzer (b) a motion sensor (c) a keypad (d) a sound sensor
25. 25.True or false: the voltmeter measures voltage. (a) False (b) True
26. 26.🔁 Is the circuit closed or open if a cell is taken out? (a) open (b) closed
27. 27.⚡ Power tells us … (a) energy used each second (b) the colour of light (c) the size of a cell (d) the length of a wire
28. 28.⏱️ A program says “wait 2250 ms”. How many seconds is that? =
29. 29.🔋 How many 3 V cells must be joined in series to give 6 V?
30. 30.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) motor (b) resistor (c) switch (d) junction
31. 31.True or false: “one out, the rest glow” is true of a parallel circuit. (a) False (b) True
32. 32.True or false: a wooden stick is a conductor. (a) True (b) False
33. 33.🌈 A resistor has the colour bands white, yellow, yellow. What is its value in kilo-ohms (kΩ)? =
34. 34.🔋 How many volts does one ordinary torch cell give? (a) 1.5 V (b) 230 V (c) 15 V (d) 0.5 V
35. 35.Which of these has no microcontroller inside? (a) a smart watch (b) a digital thermometer (c) a toy robot (d) a bicycle bell
36. 36.True or false: a toggle switch closes near a magnet. (a) True (b) False
37. 37.🔋 How many 2 V cells must be joined in series to give 14 V?
38. 38.🌈 In the resistor colour code, which number does white stand for?
39. 39.🔁 What does a variable do in a program? (a) joins two wires (b) blinks an LED (c) measures light (d) stores a value
40. 40.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =

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