Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 824 · 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 is the odd one out? (a) stay away from pylons (b) stop if a part gets hot (c) throw cells in a fire (d) keep drinks far away
2. 2.🧮 A 330 Ω resistor is joined in series with two equal 10 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
3. 3.True or false: a plain rectangle is the symbol for a resistor. (a) False (b) True
4. 4.🔁 repeat 2 times { repeat 2 times { beep } }
   How many beeps are there?
5. 5.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 6 hours?
6. 6.🔐 Is it a good or a risky habit to share only needed data? (a) good habit (b) risky habit
7. 7.🔍 Which is the odd one out? (a) a street light (b) a table fan (c) a ceiling fan (d) a mixer grinder
8. 8.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) both parts (c) the if part (d) the else part
9. 9.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 100 ms }
   How many times does the LED blink in 2 seconds?
10. 10.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) share it with friends (b) post it online (c) type it all in (d) ask a parent first
11. 11.⚠️ Is it safe to take cells out after use? (a) safe (b) not safe
12. 12.Which drawing is the symbol for a resistor? (a) a small empty box (b) a dot where wires meet (c) a circle with A inside (d) a circle with V inside
13. 13.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
14. 14.💡 2 identical bulbs are joined in series with a 4 V battery (ideal wires). How many volts does each bulb get? =
15. 15.🔍 Which is the odd one out? (a) an LED lights up (b) a temperature reading (c) an alert on the phone (d) the fan starts
16. 16.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by an iron nail. Does the bulb glow? (a) Yes (b) No
17. 17.🧾 A 200 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
18. 18.🌈 Which band is read first on a resistor? (a) the widest gap (b) the one nearest an end (c) the gold band (d) any band
19. 19.True or false: to set a strong password is a good habit. (a) True (b) False
20. 20.🔺 A current of 25 mA flows through a 400 Ω resistor. What is the voltage across it (in volts)? =
21. 21.🔋 What should you do with used-up cells? (a) bury them in soil (b) throw them in a fire (c) cut them open (d) give them for recycling
22. 22.🔺 A current of 40 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
23. 23.True or false: a resistor limits the current. (a) True (b) False
24. 24.🔺 A current of 0.1 A flows when 0.3 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
26. 26.🔌 Is a plastic straw a conductor or an insulator? (a) a conductor (b) an insulator
27. 27.True or false: a long and a short line is the symbol for a motor. (a) False (b) True
28. 28.💡 Does it save or waste electricity to leave fridge door open? (a) saves electricity (b) wastes electricity
29. 29.Which of these is an output? (a) a push button (b) a motor (c) a temperature sensor (d) a sound sensor
30. 30.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a dry cork across the gap. Does the bulb glow? (a) No (b) Yes
31. 31.⚡ A 6 W device works on 6 V. What current does it take (in amperes)? =
32. 32.🔢 To get a sensor reading onto a phone, which comes first: “it is sent by Wi-Fi” or “the sensor measures”? (a) it is sent by Wi-Fi (b) the sensor measures
33. 33.🔌 Is a safety pin a conductor or an insulator? (a) an insulator (b) a conductor
34. 34.True or false: current is measured in amperes (A). (a) True (b) False
35. 35.⚠️ Is it safe to open a phone charger? (a) safe (b) not safe
36. 36.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
37. 37.Which of these gives us electricity? (a) a mobile phone (b) a washing machine (c) a water pump (d) a bicycle dynamo
38. 38.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 1200 Ω resistor? (a) brown-red-red (b) red-brown-red (c) brown-red-orange (d) brown-red-brown
39. 39.🔌 Which part of a screwdriver should an electrician hold? (a) the plastic handle (b) the steel shaft (c) the metal tip (d) the bare end
40. 40.True or false: “one out, the rest glow” is true of a parallel circuit. (a) False (b) True

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