Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 898 · 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.🤖 Microcontroller or laptop: which one has no screen of its own? (a) laptop (b) microcontroller
2. 2.⚡ A 24 W device works on 24 V. What current does it take (in amperes)? =
3. 3.True or false: to stop a robot near walls, use a soil moisture sensor. (a) False (b) True
4. 4.🌈 A resistor has the colour bands violet, yellow, red. What is its value in kilo-ohms (kΩ)? =
5. 5.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) to hide the circuit (c) symbols are heavier (d) quick and clear for all
6. 6.🔍 Which sensor would you use to switch on lamps at dusk? (a) a distance sensor (b) a light sensor (c) a temperature sensor (d) a rain sensor
7. 7.💡 5 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulbs 4 and 5 are taken out of their holders. Does bulb 1 glow? (a) Yes (b) No
8. 8.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False
9. 9.📏 In the water-pipe picture of a circuit, voltage is like … (a) the pipe colour (b) the water pressure (c) the tap handle (d) the water tank lid
10. 10.Which drawing is the symbol for a capacitor? (a) two or more cell symbols (b) triangle, bar and arrows (c) a dot where wires meet (d) two equal parallel lines
11. 11.🔺 A 3 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
12. 12.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 1000 (b) 1024 (c) 10 (d) 100
13. 13.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) dotted circles (c) wavy lines (d) straight lines
14. 14.🤖 if (temperature > 28) { fan ON } else { fan OFF }
    The temperature sensor reads 32 °C. What happens? (a) fan OFF (b) fan ON
15. 15.🌈 A resistor has the colour bands brown, grey, red. What is its value (in ohms)?
16. 16.🤖 Where does the board keep its program when the power is off? (a) the USB cable (b) flash memory (c) the resistor (d) the power LED
17. 17.⚠️ Is it safe to stay away from pylons? (a) safe (b) not safe
18. 18.Which of these is the input? (a) decide if soil is dry (b) an LED lights up (c) the pump turns on (d) a motion sensor signal
19. 19.🧮 A 1 V battery is joined to 2 Ω and 3 Ω resistors in series. What current flows (in amperes)? =
20. 20.🧮 Resistors of 100 Ω, 68 Ω, 220 Ω and 470 Ω are joined in series. What is the total resistance (in ohms)?
21. 21.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
22. 22.🔘 A bulb and a cell are joined through 5 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
23. 23.🔍 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)?
24. 24.🔘 What does a switch do in a circuit? (a) makes electricity (b) stores current (c) opens or closes the loop (d) changes the voltage
25. 25.⏱️ A program says “wait 4750 ms”. How many seconds is that? =
26. 26.🔺 A current of 3 A flows when 6 V is joined across a resistor. What is its resistance (in ohms)?
27. 27.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is OFF and B is OFF. Does the bulb glow? (a) No (b) Yes
28. 28.Which of these is measured in amperes (A)? (a) energy used each second (b) the push of a cell (c) current (d) resistance
29. 29.🌈 A resistor has the colour bands yellow, black, yellow. What is its value in kilo-ohms (kΩ)? =
30. 30.🔢 To plan an electronics project, which is the FIRST step? (a) draw the circuit diagram (b) test it and fix it (c) list inputs and outputs (d) pick a problem to solve
31. 31.🌈 A resistor has the colour bands yellow, white, red. What is its value (in ohms)?
32. 32.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
33. 33.🔁 count = 3
    repeat 2 times { count = count + 6 }
    What is count at the end?
34. 34.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I ÷ R (c) V = I + R (d) V = I × R
35. 35.🧮 Four equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
36. 36.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
37. 37.🔍 Which is the odd one out? (a) a motor (b) a light sensor (c) a speaker (d) an LED
38. 38.🔗 Series or parallel circuit: “a break stops every bulb”? (a) series (b) parallel
39. 39.🔍 Which is the odd one out? (a) a steel coin (b) a steel spoon (c) a glass marble (d) an iron nail
40. 40.⚠️ Is it safe to use small battery cells? (a) not safe (b) safe

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