Question

When two resistors of resistances R1 and R2 are connected in parallel, the net resistance is 3 ohm
When connected in series, its value is 16 ohm. Calculate the value of R1 and R2. ​

Answer 1

Answer:

Resistance equivalent in parallel is given by R1 *R2 / (R1+R2)

Resistance equivalent in series is R1 + R2

Given R1 + R2 = 16

and R eq in parallel as 3

sustitute the above values in the first equation of parallel equivalence

we get R1*R2 = 3*16 = 48

The values of R1 and R2 are 12,4

By using basic calculations of (R1-R2)^2 = (R1 +R2)^2 - 4R1R2

R1 - R2 = sqrt(256-192) = sqrt(64) = 8

solving R1 and R2 we get r1 =12 and r2 =4