Question

Define electric resistance of a conductor? A wire of length l and resistance r is stretched so that its length is double and the area of cross section is halved. How will its resistance change and resistivity change

Answer 1

Answer:

obstruction offered to The flow of current in a conductor is called electric resistance

Explanation:

previously Resistance =row L/a

if L=2l

&a=a/2

then

r=(row)2l/a/2

r=(row)4*l/a

r=4R