Electronics Worksheet: Components and Ohm’s Law Test

Electronics lesson 20: Part 2 test: components and Ohm’s law · Set 286 · 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.🧮 Two equal 220 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
2. 2.💡 An LED is joined to a 5 V battery through a 220 Ω resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) may burn out (b) does not light (c) lights up
3. 3.🔺 A current of 20 mA flows when 6 V is joined across a resistor. What is its resistance (in ohms)?
4. 4.🔺 A 5 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
5. 5.🔺 A current of 20 mA flows when 6.6 V is joined across a resistor. What is its resistance (in ohms)?
6. 6.What does a transistor do? (a) makes a beeping sound (b) lets current go one way (c) makes things spin (d) boosts a small signal
7. 7.True or false: the push of a cell is measured in watts (W). (a) True (b) False
8. 8.True or false: on an LED, the shorter leg is the anode (+). (a) False (b) True
9. 9.🔺 A current of 2 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
10. 10.⚡ A 36 W device works on 12 V. What current does it take (in amperes)? =
11. 11.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I × R (c) V = I ÷ R (d) V = I + R
12. 12.True or false: the push of a cell is measured in ohms (Ω). (a) False (b) True
13. 13.⚡ A home appliance on the 230 V mains takes 4 A. What is its power (in watts)?
14. 14.⚡ Power tells us … (a) energy used each second (b) the colour of light (c) the size of a cell (d) the length of a wire
15. 15.True or false: a diode lets current go one way. (a) True (b) False
16. 16.📏 Voltmeter or ammeter: which one measures current? (a) voltmeter (b) ammeter
17. 17.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
18. 18.🧾 A family uses 170 units of electricity in a month and each unit costs ₹4. What is the bill (in ₹)?
19. 19.🧮 Three equal 60 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
20. 20.💡 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) lights up (c) may burn out
21. 21.🧮 Resistors of 150 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
22. 22.True or false: on an LED, the leg by the flat edge is the anode (+). (a) True (b) False
23. 23.⚡ A 2.25 W device works on 9 V. What current does it take (in amperes)? =
24. 24.🔺 A current of 1.5 A flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.🔺 A current of 25 mA flows through a 100 Ω resistor. What is the voltage across it (in volts)? =
26. 26.🧾 Which lamp gives the same light for the least power? (a) an LED lamp (b) a filament bulb (c) a candle (d) an oil lamp
27. 27.📏 Which unit measures the flow of charge? (a) ohm (Ω) (b) volt (V) (c) ampere (A) (d) watt (W)
28. 28.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
29. 29.True or false: energy used each second is measured in ohms (Ω). (a) True (b) False
30. 30.🔺 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
31. 31.🧮 Two equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
32. 32.📏 Which unit measures resistance? (a) watt (W) (b) volt (V) (c) ohm (Ω) (d) ampere (A)
33. 33.🔺 A current of 50 mA flows through a 100 Ω resistor. What is the voltage across it (in volts)? =
34. 34.🔺 A current of 40 mA flows when 8.8 V is joined across a resistor. What is its resistance (in ohms)?
35. 35.🌈 A gold fourth band on a resistor means the value may be off by … (a) 50 % (b) 25 % (c) 5 % (d) 0 %
36. 36.⚡ Which formula gives electric power? (a) P = V + I (b) P = V × I (c) P = V ÷ I (d) P = I ÷ V
37. 37.⚡ A 0.6 W device works on 6 V. What current does it take (in amperes)? =
38. 38.True or false: on an LED, the shorter leg is the cathode (−). (a) False (b) True
39. 39.🧮 Resistors of 68 Ω, 330 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
40. 40.📏 How many ohms (Ω) is 4.9 kΩ?

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