Phase angle in the DC connection

Q. In direct current , the phase angle between voltage and current is

(A) 90°

(B) 0°

Explanation :-

 The power in the DC is

                 P = V × I

Now we have to know about the phase angle between voltage and current , then the the power in the AC is

P = V × I cos (Φ)

 When Φ=90° :-

i .e.,        P = V × I (cos 90°)
               P = V × I ( 0)
               P = 0 Watts

When Φ=0° :-

i.e.,     P = V × I (cos 0°)
           P = V × I (1)
           P  = VI

So  , the phase angle between voltage and current is 0 °.