Engineering Board Exam Reviewer · Fluid Mechanics · medium
A car with a drag coefficient of 0.3 and frontal area of 2.2 m2 travels at 100 km/h in air ( = 1.2 kg/m3). What is the aerodynamic drag force?
- 3960.0 N
- 305.6 N
- 611.1 N
- 11.0 N
Answer
B. 305.6 N
Solution
V = 100/3.6 = 27.778 m/s. FD = CD A V2/2 = 0.3(2.2)(1.2)(27.778)2/2 = 305.6 N.
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