Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 170 · 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.True or false: a reed switch slides side to side. (a) True (b) False
2. 2.Which of these uses electricity? (a) a solar panel (b) a cell (c) a power station (d) a water pump
3. 3.True or false: the voltmeter measures current. (a) False (b) True
4. 4.🗺️ In an input → process → output plan, is “the fan starts” the input, the process or the output? (a) output (b) input (c) process
5. 5.Which job is done by the reset button? (a) connect sensors and LEDs (b) keeps the voltage steady (c) restarts the program (d) shows the board is on
6. 6.🔺 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
7. 7.🔍 Which sensor would you use to open blinds at sunrise? (a) a distance sensor (b) a light sensor (c) a soil moisture sensor (d) a gas sensor
8. 8.What does a push button do? (a) stays where you flip it (b) works only while pressed (c) slides side to side (d) flips up or down
9. 9.📏 Which unit measures power? (a) ohm (Ω) (b) watt (W) (c) volt (V) (d) ampere (A)
10. 10.What does a motor do? (a) has coloured bands (b) stores a little charge (c) glows using little power (d) turns a fan or wheels
11. 11.💡 5 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?
12. 12.🔺 A current of 20 mA flows when 6.6 V is joined across a resistor. What is its resistance (in ohms)?
13. 13.🧮 Resistors of 330 Ω, 33 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
14. 14.Which job needs a distance sensor? (a) water a dry plant (b) make a parking alarm (c) spot someone walking in (d) close a window in rain
15. 15.🧮 Two resistors in parallel give a total that is … (a) their sum (b) always zero (c) less than either one (d) more than either one
16. 16.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 1000 (d) 100
17. 17.🔋 What should you do with used-up cells? (a) throw them in a fire (b) cut them open (c) give them for recycling (d) bury them in soil
18. 18.✏️ In a circuit diagram, which part is drawn as one tall, one short bar? (a) junction (b) diode (c) cell (d) wire
19. 19.Which of these usually has a microcontroller inside? (a) a plain wall switch (b) a hand pump (c) a candle (d) a toy robot
20. 20.🔢 To plan an electronics project, which is the LAST step? (a) list inputs and outputs (b) test it and fix it (c) draw the circuit diagram (d) pick a problem to solve
21. 21.🔋 2 identical 3 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
22. 22.⚡ A 6 W device works on 6 V. What current does it take (in amperes)? =
23. 23.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in parallel (b) in series (c) not joined (d) by Wi-Fi
24. 24.📏 How many ohms (Ω) is 0.9 kΩ?
25. 25.🤖 Does a toy robot usually have a microcontroller inside? (a) Yes (b) No
26. 26.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
27. 27.💡 4 identical bulbs are joined in series with a 4 V battery (ideal wires). How many volts does each bulb get? =
28. 28.🔌 Why are electric wires covered in plastic? (a) plastic makes current (b) plastic is an insulator (c) to make them heavy (d) plastic is a conductor
29. 29.🔺 A current of 1 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
30. 30.🔍 Which is the odd one out? (a) a button press (b) a motion sensor signal (c) a soil moisture reading (d) an LED lights up
31. 31.🔁 count = 5
    while (count < 11) { count = count + 3 }
    How many times does the loop run?
32. 32.What does a resistor do? (a) has coloured bands (b) stores a little charge (c) smooths a wobbly supply (d) senses how bright it is
33. 33.Which of these wastes electricity? (a) unplug idle chargers (b) use LED lamps (c) use old filament bulbs (d) close the fridge quickly
34. 34.True or false: on an LED, the leg by the flat edge is the anode (+). (a) True (b) False
35. 35.True or false: an LED glows using little power. (a) False (b) True
36. 36.🧮 Two equal 20 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
37. 37.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
38. 38.🔁 count = 0
    while (count < 15) { count = count + 5 }
    How many times does the loop run?
39. 39.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
40. 40.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a pump (c) a motor (d) a buzzer

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