A piece of wire resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R’ then the ratio R/R' is

Options

A. I/25
B. I/5
C. 5
D. 25

Answer

D

Explanation

Now, resistance of each wire is R/5.
Equivalent resistance is given by `1/(R.)=5/R+5/R+5/R+5/R+5/R=25/R`
`R/(R.)=25`.
Therefore, the right option is d. 25.