A wire of given metarial having length l and ares of cross-section A has a resistance of `4 Omega`. What would be the resistance of another wire of the same meterial having length l/2 and area of cross-section 2A ?

Explanation

For first wire
`R_(1)=rhol/A=4Omega`
Now for second wire
`R_(2)= rho(l//2)/(2A)=1/4rhol/A`
`R_(2)=1/4R_(1)`
`R_(2)=1Omega`
The resistance of the new wire is `1Omega`.