Extensive testing of an experimental 2000-lb automobile reveals the aerodynamic drag force F_D and the total nonaerodynamic rolling-resistance force F_R to be as shown in the plot. Determine 

(a) The power required for steady speeds of 30 and 60 mi/hr on a level road.

(b) The power required for a steady speed of 60 mi/hr both up and down a 6-percent incline.

(c) The steady speed at which no power is required going down the 6-percent incline.

Transcribed Image Text:

80 60 FR (constant) Force, lb 40 20 Fp (parabolic). 20 40 60 80 Speed v, mi/hr