Question

Determine currents I1 , I2 and I3.

(a) -3.3A, -8.5A, 2.4A

(b) 3A, -8A, 2A

(c) 3.3A, 8.5A, -2.4A

(d) 3.2A, 8.6A, 2.3A

The question was posed to me by my school principal while I was bunking the class.

The origin of the question is Kirchhoff’s Laws topic in chapter Circuit Variables and Elements of Electric Circuits

Answer 1

Right option is (c) 3.3A, 8.5A, -2.4A

Explanation: I1 = I1 – I2 + 8 + I3 + 3

I2 – I3 = 11 -> 1

And -11 I1 – 7(I1 – I2) = 0

         -18 I1 + 7 I2 = 0 -> 2

And -11 I1 – 15 I3 =0  -> 3

      Solving I1  = 3.32A I2 = 8.5A  I3 = -2.4A.