Question

The figure below shows a part of an electric circuit. The current marked I_A​ is:

• A. 1 A
• B. 1.3 A
• C. 1.7 A
• D. 3 A

Answer 1

The Correct Option is A

Using Kirchhoff’s Current Law at point A, the sum of the currents entering the junction must equal the sum of the currents leaving the junction.
1. The incoming currents at point A are I_A and 0.2A from the top. 2. The outgoing currents are 1.2A and 0.2A downwards.
Applying Kirchhoff’s Law:
I_A +0.2 = 1.2+0.2
Simplifying:
I_A +0.2 = 1.4 ⇒ I_A=1.2A
Thus, the current I_A is 1.2A.