A wire of length L and resistance R is stretched so that its length it’s doubled. How will the (a) Resistance change (b) Resistivity change?
Length (l) is doubled & Area of cross section (A) is halved. l becomes 2l & A becomes 2A R=PAL now take l=2l,A=2A R=A/2P2l=4PAL⇒4R Resistance becomes 4 times 1) Resistivity does not depend on its length 02 Area. Hence, it does not change.
