Question

a wire of resistance 50 is drawn out so that length its is increased by twice its original length calculate its new resistance ​

Answer 1

Answer:

200

Explanation:

R' = $n^{2}$R

n=2

R' = 4 x 50 = 200

Answer 2

Answer:

R=resistivity×length/area but if length increase area also effect resistivity doesn't change because metal of wire same in both case then new equation prepare for this in which R is directly propotional to l^2 then R1/R2= L1^2/L2^2 where R1= 50 L1 =L ,L2=2L after solving 200ohm for new resistance