Two resistors, when connected in series have a total resistance of 25Ω. If they are connected in parallel, the total resistance reduces to 6Ω. Find the values of resistances.
Open in App
Solution
R1+R2=25Ω
1R1+1R2=1R ⇒R1+R2R1R2=16 ⇒6(R1+R2)=R1R2 ⇒6×25=R1R2 ⇒R1R2=150 ⇒R2=150R1...(1) Putting in (1) R1+150R1=25 ⇒R21−25R1+150=0 ⇒R21−15R1−10R1+150=0 ⇒(R1−15)(R1−10)=0 ⇒R1=15orR1=10 If R115Ω,R2=10Ω if R1=10Ω,R2=15Ω