← Part 2 test: components and Ohm’s law lesson New set →

Electronics Worksheet: Components and Ohm’s Law Test

Electronics lesson 20: Part 2 test: components and Ohm’s law · Set 592 · 40 questions
TalentJR

Remember (Find the topic, use the formula): Find the topic and the formula: V = I × R, I = V ÷ R, R = V ÷ I, P = V × I, units = W × h ÷ 1000. Change mA to A and kΩ to Ω before using a formula. Check: put your answer back into the formula.

NameDateTime takenScore ___ / 40
  1. 1.🌈 A gold fourth band on a resistor means the value may be off by … (a) 25 % (b) 0 % (c) 50 % (d) 5 %
  2. 2.📏 How many kilowatts (kW) is 850 W? =
  3. 3.⚡ Power tells us … (a) energy used each second (b) the length of a wire (c) the colour of light (d) the size of a cell
  4. 4.Which of these is measured in watts (W)? (a) the flow of charge (b) power (c) voltage (d) the push of a cell
  5. 5.Which of these is measured in ohms (Ω)? (a) the push of a cell (b) how much a part resists (c) voltage (d) power
  6. 6.📏 How many watts (W) is 3.4 kW?
  7. 7.True or false: a thermistor senses how hot it is. (a) False (b) True
  8. 8.🔺 A 12 V supply is joined across a 4 Ω resistor. What current flows (in amperes)? =
  9. 9.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
  10. 10.🧮 A 3.25 V battery is joined to 3 Ω and 10 Ω resistors in series. What current flows (in amperes)? =
  11. 11.🧮 Resistors of 50 Ω and 68 Ω are joined in series. What is the total resistance (in ohms)?
  12. 12.📏 Voltmeter or ammeter: which one measures voltage? (a) voltmeter (b) ammeter
  13. 13.🧩 Which component limits the current? (a) LED (b) motor (c) resistor (d) capacitor
  14. 14.True or false: the voltmeter is joined across a part. (a) True (b) False
  15. 15.💡 An LED is joined to a 5 V battery with no resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) may burn out (c) lights up
  16. 16.🧮 Resistors of 10 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
  17. 17.🔺 A current of 10 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
  18. 18.🧾 A family uses 150 units of electricity in a month and each unit costs ₹8. What is the bill (in ₹)?
  19. 19.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets bigger (b) stays the same (c) becomes zero (d) gets smaller
  20. 20.⚡ A device works on 6 V and takes 1 A. What is its power (in watts)? =
  21. 21.🔺 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
  22. 22.True or false: a buzzer beeps for an alarm. (a) True (b) False
  23. 23.🔍 Which is the odd one out? (a) run fans in empty rooms (b) set the AC to 24 °C (c) close the fridge quickly (d) use daylight to read
  24. 24.🧮 Resistors of 20 Ω, 50 Ω, 150 Ω and 20 Ω are joined in series. What is the total resistance (in ohms)?
  25. 25.📏 How many amperes (A) is 1920 mA? =
  26. 26.🧮 Five equal 500 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  27. 27.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
  28. 28.🧾 One “unit” on an electricity bill is … (a) 1 volt (b) 1 kilowatt-hour (kWh) (c) 1 ampere (d) 1 watt
  29. 29.Which of these saves electricity? (a) leave fridge door open (b) run fans in empty rooms (c) use daylight to read (d) leave the TV on standby
  30. 30.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 10 (b) 1024 (c) 1000 (d) 100
  31. 31.⚡ Which formula gives electric power? (a) P = V + I (b) P = I ÷ V (c) P = V ÷ I (d) P = V × I
  32. 32.🔺 A current of 40 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
  33. 33.🧮 Two equal 330 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  34. 34.🧮 Two equal 10 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  35. 35.🧮 A 2.25 V battery is joined to 5 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
  36. 36.🔺 A current of 0.1 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
  37. 37.🧮 A 330 Ω resistor is joined in series with two equal 220 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
  38. 38.⚡ A device works on 1.5 V and takes 0.1 A. What is its power (in watts)? =
  39. 39.🌈 A resistor has the colour bands violet, green, black. What is its value (in ohms)?
  40. 40.⚡ A 1 W device works on 5 V. What current does it take (in amperes)? =

Answer key

  1. 5 %
  2. 0.85
  3. energy used each second
  4. power
  5. how much a part resists
  6. 3400
  7. True
  8. 3
  9. anode (+)
  10. 0.25
  11. 118
  12. voltmeter
  13. resistor
  14. True
  15. may burn out
  16. 110
  17. 2
  18. 1200
  19. gets smaller
  20. 6
  21. V = I × R
  22. True
  23. run fans in empty rooms
  24. 240
  25. 1.92
  26. 100
  27. saves electricity
  28. 1 kilowatt-hour (kWh)
  29. use daylight to read
  30. 1000
  31. P = V × I
  32. 10
  33. 165
  34. 5
  35. 0.25
  36. 2
  37. 440
  38. 0.15
  39. 75
  40. 0.2

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