Question

a pice of wire r is cut into 5 parts these parts are connected in parallel fid equivalent resistor of this combination is r* then ration of r /r*​

Answer 1

Answer:

25:1

Explanation:

the wire is divided into 5 parts,

the resistance of wire is r

so, resistance of each part of wire would be r/5

in series the resistance of wire was r

i.e r/5 + r/5 + r/5 +r/5 +r/5 = r

5r/5=r

r = r (1)

Now, in parallel combination,

1/r* = 1/r/5 +1/r/5 +1/r/5 +1/r/5 +1/r/5

5/r +5/r +5/r +5/r +5/r

25/r = 1/ r*

r/25 = r* (2)

from 1 and 2,

ratio r/r*= r/r25

= 25r/r

=25/1

hence, 25:1 is the answer