Two wires of same material and equal length have cross sectional areas in the ratio 3:1. The thicker wire has a resistance of 10 ohm. What will be the effective resistance when these two wires are,connected in series?

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Solution

R₁ = 10Ώ , length of both wires are equal , A₁/A₂ = 3/1 (since both wires are made up of same wire so thaey have same restivity)
$\frac{R_{1}}{R_{2}} = \frac{ρ l}{\frac{A_{1}}{\frac{ρ l}{A_{2}}}} = \frac{A_{2}}{A_{1}}$ = 1/3
R₂= 3R₁= 3x10 =30Ώ
now when both the resistors are connected in series than
R_net = R₂+ R₁= 30+10 =40Ώ .

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Two wires of same material and equal length have cross sectional areas in the ratio 3:1. The thicker wire has a resistance of 10 ohm. What will be the effective resistance when these two wires are,connected in series?

R1 = 10Ώ , length of both wires are equal , A1/A2 = 3/1 (since both wires are made up of same wire so thaey have same restivity) R1R2 =ρlA1ρlA2 =A2A1 = 1/3 R2 = 3R1 = 3x10 =30Ώ ​now when both the resistors are connected in series than Rnet = R2 + R1 = 30+10 =40Ώ .