An automobile engine has a maximum power output of 70 hp, which occurs at an engine speed of 2200 rpm. A 10% power loss occurs through the transmission and differential. The rear wheels have a radius...

An automobile engine has a maximum power output of

70 hp, which occurs at an engine speed of 2200 rpm. A 10%

power loss occurs through the transmission and differential.

The rear wheels have a radius of 15.0 in. and the automobile is

to have a maximum speed of 75 mph along a level road. At this

speed, the power absorbed by the tires because of their continuous deformation is 27 hp. Find the maximum permissible drag

coefficient for the automobile at this speed. The car’s frontal

area is 24.0 ft2.