JEE Main2004PhysicsCurrent ElectricityActual
The resistance of the series combination of two resistances is S . When they are joined in parallel through total resistance is P . If S=n P , then the minimum possible value of n is
Options
- A4
- B3
- C2
- D1
Correct answer
A. 4
Step-by-step solution
Let resistances be R₁ and R₂ So, S=R₁+R₂ ; aligned & P = R ₁ R ₂ R ₁+ R ₂ & ~S = nP & R ₁+ R ₂= nR ₁ R ₂ R ₁+ R ₂ & ( R ₁+ R ₂ )^2= nR ₁ R ₂ aligned If R₁=R₂ , so minimum value of n=4 .