Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 859 · 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 solar panel changes which kind of energy into electricity? (a) chemical energy (b) wind energy (c) light energy (d) sound energy
2. 2.🔘 A bulb and a cell are joined through 5 switches on 5 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
3. 3.True or false: on an LED, the shorter leg is the anode (+). (a) False (b) True
4. 4.⚠️ What protects home wiring by melting or tripping when too much current flows? (a) a bulb (b) a plug top (c) a long wire (d) a fuse or MCB
5. 5.💡 A blue LED uses 3 V and should get 20 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
6. 6.True or false: to use a cable with cuts is safe. (a) True (b) False
7. 7.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
8. 8.🔘 A cell and a bulb are joined to 3 side-by-side paths with one switch on each path — A, B and C (parallel). A is ON, B is ON and C is OFF. Does the bulb glow? (a) No (b) Yes
9. 9.⏱️ repeat 10 times { buzzer ON; wait 500 ms; buzzer OFF; wait 500 ms }
   How many milliseconds does this take in all?
10. 10.Which of these is not safe? (a) use small battery cells (b) build with an adult near (c) keep drinks far away (d) use a cable with cuts
11. 11.📶 A pin that reads a push button is set as … (a) a battery (b) an output (c) a resistor (d) an input
12. 12.🔁 repeat 4 times { repeat 3 times { beep } }
    How many beeps are there?
13. 13.⚡ A device works on 1.5 V and takes 0.5 A. What is its power (in watts)? =
14. 14.Which of these is the input? (a) an LED lights up (b) a button press (c) decide if soil is dry (d) check if temp > 30
15. 15.⚡ What does a school bell mainly change electricity into? (a) movement (b) light (c) heat (d) sound
16. 16.⏱️ How many milliseconds are in 1 second? (a) 100 (b) 10 (c) 1000 (d) 60
17. 17.True or false: a microcontroller runs one small program. (a) False (b) True
18. 18.💡 Why does an LED need a resistor in series? (a) to change its colour (b) to make it brighter (c) to limit the current (d) to store charge
19. 19.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a steel coin across the gap. Does the bulb glow? (a) No (b) Yes
20. 20.🧮 Two equal 220 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
21. 21.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) ammeter (b) motor (c) resistor (d) bulb
22. 22.💡 What does LED stand for? (a) light-emitting diode (b) large electric dial (c) low energy device (d) light energy dial
23. 23.💡 3 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
24. 24.⚙️ Which actuator would you use to beep an alarm? (a) a servo motor (b) a pump (c) a display (d) a buzzer
25. 25.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a rubber band. Does the bulb glow? (a) Yes (b) No
26. 26.🧩 Which component limits the current? (a) buzzer (b) motor (c) LED (d) resistor
27. 27.🔍 Which is the odd one out? (a) keep drinks far away (b) stop if a part gets hot (c) fly kites in open fields (d) touch a switch when wet
28. 28.Which of these gives us electricity? (a) a computer (b) a water pump (c) a bicycle dynamo (d) a television
29. 29.🌈 Which band is read first on a resistor? (a) the widest gap (b) the gold band (c) any band (d) the one nearest an end
30. 30.Which of these is measured in ohms (Ω)? (a) energy used each second (b) the push of a cell (c) power (d) resistance
31. 31.🧮 Two equal 330 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
32. 32.True or false: a laptop runs one small program. (a) False (b) True
33. 33.True or false: how much a part resists is measured in ohms (Ω). (a) True (b) False
34. 34.⏱️ repeat 9 times { buzzer ON; wait 800 ms; buzzer OFF; wait 100 ms }
    How many milliseconds does this take in all?
35. 35.🔁 total = 0
    for i = 1 to 11 { total = total + i }
    What is total at the end?
36. 36.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = R ÷ I (c) V = I ÷ R (d) V = I × R
37. 37.📏 In the water-pipe picture of a circuit, resistance is like … (a) the water pressure (b) a narrow pipe (c) the flow of water (d) a bigger tank
38. 38.🤖 Which is a safe power source for a beginner microcontroller board? (a) a 230 V cable (b) USB or a 9 V battery (c) a wall socket directly (d) bare mains wires
39. 39.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. How many bulbs glow?
40. 40.🔐 Is it a good or a risky habit to set up with a parent? (a) risky habit (b) good habit

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