Question

A Toyota Prius has the following attributes: Drag Coefficient Ca = 0.24, Frontal Area Af = 25.83 ft?, weight = 3064 lb, and Speed = 90 mph. Use air density p = 0.002378 slugs/ft3.

Answer 1

So 0.0063 V3 + 0.208V2 + 153.2V - 15,400 =0 This is a cubic equation, which have three roots. After solving this equation, the three roots are Vi = 75.28226 Va = -54.14907 +j(171.86701) V3 = -54.14907 - 3(171.86701) is real root & other are imaginary roots Hence max. speed is = 1, = 75.28 ft/s Conclusion The maximum speed of car is 75.28 ft,

Given that Drag Drag co Coefficient c = 0.24 frontal Area A = 25.83ft² weightwt 3064 lb, grado 4%, power = Ziemp & altitude - 5000ft air density S=0.002045 Slug/ft? find Maximum speed ) solution a)Power required for overcoming acrodynamic resistance is (P= I Co AG V3 Power required for overcoming rolling resistance is = (1+2) x 0.01 X W XV - Power required for overcoming grade resistance is [P₂ = WGVI - G= Grade So Total power P = P + P2 + P3 - 9 Now for maximum speed, use the eq0,cq@, eq 4 eq@ & put the all data So p = 550 x2* 0.00 2045 x 0.24x 25.83XV + 0.01xe1tv. 1x 30648V & Po 3064x tau av 154@@= 0.0063V3+ (30.64+0.2089 x V + 12.2.56V' 15408 = 0.0063V3 + 0.208V2 + 153.2V : 1 hp = 550 ft-lb/}