Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 37 · 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.🔁 Is the circuit closed or open if the switch is OFF? (a) open (b) closed
2. 2.🔺 A current of 10 mA flows when 1 V is joined across a resistor. What is its resistance (in ohms)?
3. 3.Which of these is true of a series circuit? (a) each gets the full volts (b) bulbs share the voltage (c) many paths for current (d) used in house wiring
4. 4.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
5. 5.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
6. 6.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) gets bigger (c) gets smaller (d) stays the same
7. 7.🔦 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) Yes (b) No
8. 8.🔺 A current of 40 mA flows when 10 V is joined across a resistor. What is its resistance (in ohms)?
9. 9.🌐 Is a battery torch an IoT device? (a) an IoT device (b) not an IoT device
10. 10.🔋 2 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
11. 11.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = V + I (c) P = I ÷ V (d) P = V × I
12. 12.🔺 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
13. 13.🔦 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 steel coin. Does the bulb glow? (a) Yes (b) No
14. 14.Which job needs a servo motor? (a) open a gate to 90° (b) beep an alarm (c) show a status light (d) show the temperature
15. 15.⚠️ Is it safe to fly a kite near wires? (a) not safe (b) safe
16. 16.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = V ÷ I (c) R = I ÷ V (d) R = V + I
17. 17.💡 5 identical bulbs are joined in series with a 12.5 V battery (ideal wires). How many volts does each bulb get? =
18. 18.Which of these mainly makes movement? (a) a room heater (b) an electric iron (c) a ceiling fan (d) a traffic signal
19. 19.⏱️ A program says “wait 250 ms”. How many seconds is that? =
20. 20.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
21. 21.Which of these is a conductor? (a) a metal paper clip (b) a glass marble (c) a rubber band (d) a paper strip
22. 22.Which of these is the input? (a) check if temp > 30 (b) count button presses (c) a light level reading (d) an LED lights up
23. 23.💡 5 identical bulbs are joined in series with a 5 V battery (ideal wires). How many volts does each bulb get? =
24. 24.🌐 Is a Wi-Fi weather station an IoT device? (a) an IoT device (b) not an IoT device
25. 25.🧮 Resistors of 47 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
26. 26.🌈 In the resistor colour code, which number does grey stand for?
27. 27.True or false: a slide switch slides side to side. (a) False (b) True
28. 28.What does a reed switch do? (a) works only while pressed (b) stays where you flip it (c) springs back when let go (d) closes near a magnet
29. 29.🧮 Four equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
30. 30.⚠️ About how many volts do home sockets in India supply? (a) 12 V (b) 230 V (c) 9 V (d) 1.5 V
31. 31.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) the if part (c) the else part (d) both parts
32. 32.Which of these is measured in volts (V)? (a) voltage (b) current (c) resistance (d) how much a part resists
33. 33.🧩 Which component limits the current? (a) resistor (b) buzzer (c) fuse (d) capacitor
34. 34.True or false: the voltmeter measures voltage. (a) False (b) True
35. 35.📏 Which unit measures voltage? (a) volt (V) (b) watt (W) (c) ohm (Ω) (d) ampere (A)
36. 36.Which of these has no microcontroller inside? (a) a washing machine (b) a candle (c) a digital alarm clock (d) a microwave oven
37. 37.🧩 A capacitor in a circuit can … (a) measure heat (b) make light (c) store charge briefly (d) spin a wheel
38. 38.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?
39. 39.🔋 6 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)? =
40. 40.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
    The temperature is 15 °C. What is shown? (a) Cool (b) Warm (c) Hot

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids