Question

From some instruments current measured is `I=10.0amp`, potential different measured is `V=100.0 V`, length of wire is `31.4 cm`, and diameter of wire is `2.00mm` (all in correct significant figure). The resistivity of wire (in correct significant figures)will be (use `pi=3.14`)
A. `1.00xx10^(-4)Omega-m`
B. `1.0xx10^(-4)Omega-m`
C. `1xx10^(-4)Omega-m`
D. `1.000xx10^(-4)Omega-m`

Answer 1

Correct Answer - A
`p=(piD^(2))/(4L)=(V)/(I)=((3.14)(2.00xx10^(-3))^(-2))/(4(0.314))((100.0)/(10.0))`
and answer should be in three `S.F`
so `p=1.00xx10^(-4)Omega-m`