Explanation:
a)
R total= R1 + R2 + R3 = 50 + 25 + 10 = 85
I = V/R total = 27/85 A
V1 = IR1 = 27/85 × 50 = 270/17 v
V2 = IR2 = 27/85 × 25 = 135/17 v
V3 = IR3 = 27/85 × 10 = 54/17 v
b)
R1,2 = R1.R2/(R1+R2) = 50 × 25/75 = 50/3
R total = R1,2.R3/(R1,2 + R3) = 50/3 × 10/( 50/3 + 10) = 500/80 = 25/4
I = V/R = 27/(25/4) = 108/25 A
V1 = V2 = V3 = V = 27 v
I1 = V/R1 = 27/50 A
I2 = V/R2 = 27/25 A
I3 = V/R3 = 27/10 A