Consider a 1200 kg car and solve the questions below
a) Find the cost of transportation (per kilometre) in units of MJ/km if this car drives 1 kilometer at an average speed of 15 m/s(54kph). Draw a simple car showing the cross section and 3 arrows to identify the direction of the movement and forces. Assume: D=21% engine; stops and starts 5 times per km (city driving); Cr=0.025 cross section is 3.5 m by 2.55 m;Cd=0.32; air density 1.29 kg/m3
b) Convert this cost of transportation from MJ/km into fuel expense units of litres of gasoline per 100 km, note, it needs to be per 100 km not 1 km. Gasoline has density 730 g/L Gasoline energy content 47MJ/kg Water density 1000 kg/m3 Water specific heat capacity 4186 J/kg/K 1 tonne =1000 kg