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100 Build Your Own Electric VehicleF a(in pounds) F a(in pounds) F a(in pounds)a (in mph/sec) a'= a/21.95 C i= 1.06 C i= 1.1 C i= 1.21 0.046 48.3 50.1 54.72 0.091 96.6 100.2 109.33 0.137 144.8 150.3 164.04 0.182 193.1 200.4 218.65 0.228 241.4 250.5 273.36 0.273 289.7 300.6 328.07 0.319 338.0 350.7 382.68 0.364 386.3 400.8 437.39 0.410 434.5 450.9 491.910 0.455 482.8 501.0 546.6Ta b l e 5-1 Acceleration F orce, F a(in pounds), for Different V alues of C iTo use Table 5-1 with your EV, multiply by the ratio of your vehicle weight and usethe C i5 1.06 column for lighter vehicles and C i5 1.2 column for heavier ones. Forexample, the 3,800-lb. Ford Ranger pickup truck of Chapter 10 would require 5 mph/sec 5 3.8 3 273.3 5 1038.5 lbs.Weight and ClimbingWhen you go hill climbing, you add another force:F h5 Wsin fwhere F his hill-climbing force, W is vehicle weight in pounds, and f is angle of inclineas shown in Figure 5-2. The degree of the incline—the way hills or inclines are commonlyreferred to—is different from the angle of the incline, but Figure 5-2 should clear up anyconfusion for you. Notice that sin f varies from 0 at no incline (no effect) to 1 at 90degrees; in other words, the full weight of the vehicle is trying to pull it back down theincline. Again, weight is directly involved, acted upon this time by the steepness of thehill.Degree of incline 5 1% 5 1 foot 5 Rise100 feet RunAngle of incline, O 5 Arc tan Rise 5 Arc tan 0.01 5 about 0 degrees 34 minutesRunFi g u r e 5-2 Angle of incline defined.