Question

please anwer step by step .. Q. A wire has a resistence R is cut into two equal pieces.The two parts are joined in parallel .What is the resistence of the combination??

Answer 1

Wire has resistance R.
When cut into two equal parts, resistance becomes R/2.

Parallel resistance combination = 1/Req = 1/R1 + 1/R2

R1 =  R2 = R/2

1/(R/2) + 1/(R/2) = 1/Req

2/R + 2/R =1/Req

2R + 2R/R squared = 1/Req

4R/R x R = 1/Req

4/R = 1/Req

R equivalent = R/4

Resistance of combination = R/4

Answer 2

as given wire is cut into equal parts,
the resistances will be of both R/2, R/2.
then,
1/R'=1/R/2 +1/R/2
1/R'= 2/R + 2/R
1/R'= 2+2/R
1/R' = 4/R
R' = R/4
Required Answer.