calculate the equivalent resistance of the circuit shown bel

calculate the equivalent resistance of the circuit shown below. R1=5.5 ohms, R2=11.5 ohms, R3=1.5 ohms, and R4=3.0 ohms, R5=13.0 ohms, and R6=7.0 ohms

Solution

remember these about Combination of Resistors

if R1 and R2 are the resistances connected in series then effective resiatcne

Rnet = R1+R2

if R1 and R2 are connected in parallel,

then 1/Rnet =1/R1 +1/R2 or

Rnet = R1R2/(R1+R2)

here

R1 and R2 are in parallel

so

1/R12 = 1/5.5 + 1/11.5

R12 = 3.73 Ohms

R12 is in series with R3

so

R123 = R12+ R3 = 3.73 + 1.5 = 5.23 ohms ---------------------1

R5 and R6 are in parallel

so

1/R56 = 1/R5 +1/R6 = 1/13 + 1/7

R56 = 4.56 ohms

R4 and R56 are in series

R456 = R4 + R56 = 4.56 + 3

R456 = 7.56 ohms ------------------------------------------2

R123 and R456 are in parallel

so

1/Rnet = 1/R123 + 1/R456

1/Rnet = 1/7.56 + 1/5.23

Rnet = 3.1 ohms