The Wind Speed of the Air Flowing Over a 16-Cm-Diameter

Multiple Choice

The wind speed of the air flowing over a 16-cm-diameter outside mirror is significantly higher than the speed of a vehicle. If the pressure on the front of the mirror is assumed to be
Stagnation pressure and the pressure on the rear is assumed to be atmospheric, the power
Needed to move the mirror, if the air velocity around the mirror is 30 m/s, is nearest:

A) 0.44 hp
B) 0.39 hp
C) 0.34 hp
D) 0.29 hp