Answers

2014-04-24T17:36:31+05:30
R= \frac{pl}{A}=29
when l'=2l
A'=A/2
so R'= \frac{pl'}{A'}=4 \frac{pl}{A}=4(29)=116
so new resitance is 116 ohm
0
2014-04-24T20:04:29+05:30
R = pl/A

p=density , l=length , A = area

Multiplying l to both numerator and denominator,

R = pl^2 / V

V = Volume

R proportional to l^2

So when l is doubled , R becomes 4 times.

So R=116 ohm
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