four resistor of resistance 1ohms2ohm3 ohm 5ohm are connected in series and afterward in parallel calculate the combined resistance in each case

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series ... 1Ω + 2Ω + 3Ω + 5Ω = R Ω

parallel ... (1 / 1Ω) + (1 / 2Ω) + (1 / 3Ω) + (1 / 5Ω) = 1 / R
... LCD is 30 ... (30 / 30) + (15 / 30) + (10 / 30) + (6 / 30) = 1 / R
... 61 / 30 = 1 / R ... R = 30 / 61 Ω

Did you know?

Did you know that when resistors are connected in series, their resistances are simply added up? In the case of four resistors with resistances of 1 ohm, 2 ohms, 3 ohms, and 5 ohms, when connected in series, the combined resistance would be 1 + 2 + 3 + 5 = 11 ohms. On the other hand, when these four resistors are connected in parallel, the combined resistance is calculated differently. The reciprocal of the combined resistance is equal to the sum of the reciprocals of the individual resistances. In this case, it would be 1/1 + 1/2 + 1/3 + 1/5 = 11/30. By taking the reciprocal of this value, we find that the combined resistance when connected in parallel would be approximately 2.73 ohms. Understanding how resistors behave when connected in series or parallel is fundamental in analyzing and designing electrical circuits.