A wire of Length L and resistance R is stretched so that its length is doubled and the area of cross section is halved ,How will its
a. resistance change ?
b.resistivity change

Answer :

limzy
If a wire of Length L and resistance R is stretched so that its length is doubled and the area of cross section is halved then
a. its resistance will increase 4 times.
b. its resistivity will not change as it does not depend on length and area, its a property of the material
Resistance is directly proportional to length is inversely proportional to the area of cross section.
if length increases twice, resistance increases twice.
if increase of length and area happens, resistance increases four times