A wire of a certain material is stretched slowly by ten percent. Its new resistance and specific resistance become respectively.

Options

A. both remain the same
B. 1.1 times, 1.1 times
C. 1.2 times, 1.1 times
D. 1.21 times, same

Answer

D

Explanation

`R=(phil)/(A)`
Now, `l=l+(l)/(10)=(11l)/(10)`
and therefore, `A=(10A)/(11)`
So, `R'=(Pxx((11l)/(10)))/(((10A)/(11)))=(phil)/(A)xx((11)^(2))/((10)^(2))=1.21R`
Now resistance becomes 1.21 times of initial and specific resistance is the intrinsic property so remains same.