Question

a wire of length L and resistance R is stretched to triple its length how will its resistance change and resistivity change​

Answer 1

Answer:The new resistance will be thrice the old resistance and resistivity will remain same.

Explanation:We know that

R=p.l/A

If length is tripled ,then new resistance will be

R'=p.3l/A

R'/R=p.3l/A*A/p.l

R'/R=3

R'=3R...

And if the nature and the material of the conductor is same resistivity will remain unchanged..

Hope It Helps..

Answer 2

R=ρL/A

Resisitivity will remain same as it depends only on the material used and not on the dimensions.

L'=3L

therefore

R'=ρ3L/A

=3R

resistance becomes thrice of the original value.

Hope this helps.