A simple measurement of automobile drag can be found by an unpowered coast down on a level road with no wind. Assume constant rolling resistance. For an automobile of mass 1500 kg and frontal area 2 m2, the following velocity-versus-time data are obtained during a coast down:
t, s: 0.00 10.0 20.0 30.0 40.0
V, m/s: 27.0 24.2 21.8 19.7 17.9
Estimate (a) the rolling resistance and (b) the drag coefficient. This problem is well suited for digital-computer analysis but can be done by hand also.