In figure, the current I4 is

Question: In figure, the current I4 is
[A].

10 ∠0

[B].

5 ∠90°

[C].

5 ∠270°

[D].

10 ∠90°

Answer: Option B

Explanation:

I4 = I1 + I2 + I3

or I4 = 5∠90° + 5∠0 + 5∠180° = 5∠90°.