Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 572 · 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 safe? (a) use a cable with cuts (b) touch a fallen wire (c) touch a switch when wet (d) take cells out after use
2. 2.🔁 count = 3
   repeat 5 times { count = count + 4 }
   What is count at the end?
3. 3.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) both lines (c) the longer line (d) the shorter line
4. 4.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 6400 Ω resistor? (a) blue-yellow-brown (b) blue-yellow-red (c) blue-yellow-orange (d) yellow-blue-red
5. 5.💡 A battery lights 2 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
6. 6.⏱️ A program says “wait 1750 ms”. How many seconds is that? =
7. 7.🔍 Which is the odd one out? (a) an electric toy car (b) a school bell (c) a ceiling fan (d) a mixer grinder
8. 8.True or false: a circle with a cross is the symbol for a bulb. (a) False (b) True
9. 9.🤖 Does a digital alarm clock usually have a microcontroller inside? (a) No (b) Yes
10. 10.Which drawing is the symbol for a junction? (a) a dot where wires meet (b) triangle, bar and arrows (c) a plain rectangle (d) one tall, one short bar
11. 11.🔺 A current of 40 mA flows through a 300 Ω resistor. What is the voltage across it (in volts)? =
12. 12.🔍 Which is the odd one out? (a) a copper wire (b) a plastic ruler (c) a brass key (d) aluminium foil
13. 13.🤖 “if (A AND B)” is true when … (a) only B is true (b) only A is true (c) both are false (d) both A and B are true
14. 14.🔋 3 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)? =
15. 15.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) stay the same (c) zero (d) bigger
16. 16.🔋 7 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
17. 17.🧾 One “unit” on an electricity bill is … (a) 1 watt (b) 1 volt (c) 1 ampere (d) 1 kilowatt-hour (kWh)
18. 18.🔦 A circuit has a new cell, a bulb with a broken filament 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
19. 19.Which of these is a risky habit? (a) accept every permission (b) share only needed data (c) cover unused cameras (d) install software updates
20. 20.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I × R (c) V = I ÷ R (d) V = R ÷ I
21. 21.💡 4 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. How many bulbs glow?
22. 22.Which drawing is the symbol for an ammeter? (a) a circle with a cross (b) a circle with A inside (c) a straight line (d) a long and a short line
23. 23.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) two (c) none (d) one
24. 24.⏱️ loop forever { LED ON; wait 450 ms; LED OFF; wait 1000 ms }
    How many milliseconds does one blink (ON + OFF) take?
25. 25.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the input (b) the battery (c) the output (d) the process
26. 26.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a glass marble across the gap. Does the bulb glow? (a) No (b) Yes
27. 27.⚠️ Is it safe to fly a kite near wires? (a) not safe (b) safe
28. 28.True or false: a safety pin is a conductor. (a) False (b) True
29. 29.🔋 2 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
30. 30.🔋 What is a battery? (a) a switch with a lid (b) one single wire (c) two or more cells joined (d) a kind of bulb
31. 31.Which of these is an input? (a) a motor (b) an LED (c) a keypad (d) a small display
32. 32.Which of these is a conductor? (a) a cotton thread (b) a safety pin (c) a plastic ruler (d) a wooden stick
33. 33.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
34. 34.🔺 A current of 0.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
35. 35.True or false: to use LED lamps wastes electricity. (a) True (b) False
36. 36.🔍 Which is the odd one out? (a) count button presses (b) decide if soil is dry (c) compare with a limit (d) the fan starts
37. 37.🔍 Which is the odd one out? (a) fly kites in open fields (b) use mains for a project (c) touch a fallen wire (d) touch a switch when wet
38. 38.True or false: a toaster mainly gives out light. (a) False (b) True
39. 39.⏱️ loop forever { LED ON; wait 450 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 1 second?
40. 40.⚠️ Is it safe to climb an electric pole? (a) safe (b) not safe

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