Question

R1 = 1Ω, R2 = 3Ω, R3 = 5Ω and R4 = 7Ω connected in series. Total voltage = 20V, Current I, V2 =?

(a) I = 1.23, V2 = 3.75

(b) I = 1.25, V2 = 3.75

(c) I = 1.15, V2= 3.73

(d) I = 1.16, V2 = 3.72

The question was asked in a job interview.

My doubt stems from The Voltage Divider and Current Divider Circuits in portion Simple Resistive Circuits of Electric Circuits

Answer 1

Right choice is (b) I = 1.25, V2 = 3.75

Explanation: I = 20/ 1 + 3 + 5 + 7 = 1.25A

    V2 = V. R2 / R1 + R2 + R3 + R4

     = 20(3)/16

   = 3.75V.