Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 657 · 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.📏 In the water-pipe picture of a circuit, voltage is like … (a) the water tank lid (b) the tap handle (c) the pipe colour (d) the water pressure
2. 2.🔺 A current of 10 mA flows through a 100 Ω resistor. What is the voltage across it (in volts)? =
3. 3.🔺 A current of 0.5 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
4. 4.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a buzzer (c) a servo motor (d) a pump
5. 5.⏱️ A program says “wait 1000 ms”. How many seconds is that? =
6. 6.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
   The temperature is 11 °C. What is shown? (a) Cool (b) Warm (c) Hot
7. 7.🔁 x = 4
   repeat 5 times { x = x × 2 }
   What is x at the end?
8. 8.🤖 if (moisture < 50) { pump ON } else { pump OFF }
   The soil moisture sensor reads 39 %. What happens? (a) pump OFF (b) pump ON
9. 9.True or false: a straight line is the symbol for a resistor. (a) True (b) False
10. 10.🌈 A resistor has the colour bands grey, white, brown. What is its value (in ohms)?
11. 11.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
12. 12.🌈 A resistor has the colour bands grey, grey, red. What is its value in kilo-ohms (kΩ)? =
13. 13.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
14. 14.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) nothing at all (d) the final price
15. 15.True or false: a microwave oven has no microcontroller inside. (a) True (b) False
16. 16.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) when both are ON (c) never (d) when both are OFF
17. 17.Which of these means the circuit is closed? (a) a cell is taken out (b) the bulb is unscrewed (c) a wire is cut (d) the loop is complete
18. 18.True or false: if a wire is cut, the circuit is open and no current flows. (a) False (b) True
19. 19.🔺 A current of 0.2 A flows when 0.4 V is joined across a resistor. What is its resistance (in ohms)?
20. 20.True or false: a long and a short line is the symbol for a cell. (a) False (b) True
21. 21.🧾 A family uses 110 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
22. 22.🌈 A gold fourth band on a resistor means the value may be off by … (a) 50 % (b) 25 % (c) 5 % (d) 0 %
23. 23.💡 4 identical bulbs are joined in parallel across a 3 V battery (ideal wires). How many volts does each bulb get? =
24. 24.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a motor (b) a display (c) a buzzer (d) an LED
25. 25.True or false: a toggle switch flips up or down. (a) False (b) True
26. 26.Which of these mainly makes sound? (a) an electric toy car (b) a loudspeaker (c) a street light (d) a night lamp
27. 27.🌈 A resistor has the colour bands white, yellow, red. What is its value in kilo-ohms (kΩ)? =
28. 28.⚡ A device works on 12 V and takes 3 A. What is its power (in watts)? =
29. 29.🧮 Resistors of 47 Ω, 220 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
30. 30.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
31. 31.🧾 A family uses 60 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
32. 32.💡 What happens if an LED is put in backwards? (a) it changes colour (b) it makes a sound (c) it lights brighter (d) it does not light
33. 33.What does a fuse do? (a) senses how hot it is (b) blows if current is high (c) makes a beeping sound (d) turns a fan or wheels
34. 34.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
35. 35.📶 A pin set LOW gives about … (a) 5 V (b) 9 V (c) 1.5 V (d) 0 V
36. 36.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
37. 37.Which drawing is the symbol for a cell? (a) a circle with V inside (b) a long and a short line (c) many long-short pairs (d) a straight line
38. 38.Which job needs a pump? (a) move water to plants (b) show a status light (c) spin a robot’s wheels (d) beep an alarm
39. 39.🔁 What must there be for a current to flow? (a) a broken path (b) a plastic gap (c) a complete loop (d) one loose end
40. 40.🔋 Does a power station give electricity or use electricity? (a) gives electricity (b) uses electricity

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