Question

pliz guys I want answer fast and correct ​

Answer 1

Answer:

length = 7.5 cm

Explanation:

let ' Ri ' be the resistance of iron wire ,

' Rs ' be the resistance of silver wire

and ' A ' be the area of both the wires.( they have equal area because they have equal thickness )

Given, Ri = Rs _________________ (i)

since the length is given as 12cm = 0.12m

Ri = rho × length / area

= 10 × 10^-8 × 0.12 / A

Ri = 1.2 × 10^-8 / A _________________ (ii)

let length of silver wire be ' l ' m .

Rs = rho × length / area

Rs = 16 × 10^ -8 × l / A _______________ (iii)

from (i),(ii) and (iii) ,

1.2 × 10^-8 / A = 16 × 10^-8 × l / A

10^-8 and A can be cancelled on both sides,

=> 1.2 = 16l

=> l = 1.2 / 16

= 0.075 m

= 7.5 cm

Hope this will help you.

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