40) A wire of resistanceroof 4w is bent in form of a circle.Find the equivalent resistance across
It's diameter.
Answers
QUESTION :-
A wire of resistance 4 ohm is bent in the form of a circle . Find the equivalent resistance across its diameter .
SOLUTION :-
Resistance of the wire = 4 ohm
according to the question ,
the wire is bent in the form of a circle .
Now,
we have to find the equivalent resistance across its diameter
The resistance of one half of the circle would be equal to 2 ohm and the other part would also be 2 ohm.
both the 2 ohm resistances are in parallel combination.
In parallel combination,
equivalent resistance ( R eq )
1 / R eq = 1 / R₁ + 1 / R₂
here,
R₁ = 2 ohm
R₂ = 2 ohm
now, putting the values in the above formula
1 / R eq = 1 / 2Ω + 1 / 2Ω
⇒ 1 / R eq = ( 1+1) / 2Ω
⇒ 1 / R eq = 2 / 2Ω
⇒ R eq = 1 Ω
Therefore,
The equivalent resistance across its diameter is 1 ohm.