Q. The aerodynamic drag on a sports car depends on its shape. The car has a drag coefficient of 0.1 with the windows and the roof closed. With the windows and the roof open, the drag coefficient becomes 0.8. The car travels at 44 km/h with the windows and roof closed. For the same amount of power needed to overcome the aerodynamic drag, the speed of the car with the windows and roof open (round off to two decimal places), is__________km/h
Ans: 22 km/h
Sol:
Drag coefficient of car = 0.1 (Cd) {window roof closed}
Cd = 0.8 (windows and roof open)
V1 = 44 km/h {windows and roof closed}
To find V2 {windows and roof open} for same amount of power.