Q.

A wire of resistance R is cut into 8 equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. Then these two sets are added in series. The net effective resistance of the combination is            [2025]

1 R16  
2 R8  
3 R64  
4 R32  

Ans.

(1)

Resistance of each part, r=R8

R1=R2=r4=R32

R1 and R2 are in series

   Req=R1+R2=R32+R32=R16