Electronics Worksheet: Components and Ohm’s Law Test

Electronics lesson 20: Part 2 test: components and Ohm’s law · Set 922 · 40 questions

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.

1. 1.🌈 A resistor has the colour bands brown, blue, orange. What is its value in kilo-ohms (kΩ)? =
2. 2.💡 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) may burn out (b) does not light (c) lights up
3. 3.True or false: a resistor has coloured bands. (a) True (b) False
4. 4.True or false: the flow of charge is measured in volts (V). (a) False (b) True
5. 5.🧮 A 4 V battery is joined to 2 Ω and 2 Ω resistors in series. What current flows (in amperes)? =
6. 6.🧩 Which part changes electrical energy into sound? (a) a capacitor (b) a resistor (c) a diode (d) a buzzer
7. 7.🔺 A current of 1 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
8. 8.📏 How many milliamperes (mA) is 0.62 A?
9. 9.💡 What happens if an LED is put in backwards? (a) it makes a sound (b) it lights brighter (c) it changes colour (d) it does not light
10. 10.🌈 Which band is read first on a resistor? (a) the gold band (b) any band (c) the one nearest an end (d) the widest gap
11. 11.📏 In the water-pipe picture of a circuit, current is like … (a) the water pressure (b) the pipe colour (c) the flow of water (d) a narrow pipe
12. 12.🧮 A 22 Ω resistor is joined in series with two equal 100 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
13. 13.🔺 A current of 0.2 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
14. 14.🌈 A resistor has the colour bands brown, green, black. What is its value (in ohms)?
15. 15.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
16. 16.🔺 A current of 1.5 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
17. 17.📏 In the water-pipe picture of a circuit, resistance is like … (a) the flow of water (b) a narrow pipe (c) a bigger tank (d) the water pressure
18. 18.🔺 A 20 V supply is joined across a 20 Ω resistor. What current flows (in amperes)? =
19. 19.True or false: a buzzer makes a beeping sound. (a) False (b) True
20. 20.🔺 A 0.4 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
21. 21.📏 How many kilo-ohms (kΩ) is 2800 Ω? =
22. 22.⚡ Power tells us … (a) energy used each second (b) the colour of light (c) the length of a wire (d) the size of a cell
23. 23.🔺 A current of 20 mA flows when 5 V is joined across a resistor. What is its resistance (in ohms)?
24. 24.🧮 Resistors of 68 Ω and 47 Ω are joined in series. What is the total resistance (in ohms)?
25. 25.🔺 A current of 50 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
26. 26.📏 How many ohms (Ω) is 2.6 kΩ?
27. 27.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
28. 28.🔺 A 5 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =
29. 29.🧮 A 220 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)?
30. 30.🌈 A resistor has the colour bands grey, yellow, orange. What is its value in kilo-ohms (kΩ)? =
31. 31.📏 Which unit measures voltage? (a) watt (W) (b) ampere (A) (c) ohm (Ω) (d) volt (V)
32. 32.💡 An LED is joined to a 9 V battery through a 330 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) lights up (b) may burn out (c) does not light
33. 33.🔺 A current of 1 A flows through an 8 Ω resistor. What is the voltage across it (in volts)? =
34. 34.🔺 A current of 2.5 A flows when 25 V is joined across a resistor. What is its resistance (in ohms)?
35. 35.📏 How many ohms (Ω) is 5.3 kΩ?
36. 36.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 6900 Ω resistor? (a) blue-white-red (b) blue-white-brown (c) white-blue-red (d) blue-white-orange
37. 37.True or false: the voltmeter measures current. (a) True (b) False
38. 38.🧮 A 22 Ω resistor is joined in series with two equal 200 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
39. 39.🧩 Which component stores a little charge? (a) capacitor (b) diode (c) transistor (d) motor
40. 40.📏 How many ohms (Ω) is 6.5 kΩ?

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