Question: ODE plots, calculating initial velocity of a baseball

Consider the problem of a hard-hit baseball. The air-friction drag on a baseball is approximately given by the following formula

and subsequent differential equations : 

d2v_x:=-((C_d)*rho*Pi*(r^2)*(v_x)*sqrt((v_x)^2 +(v_y)^2))/(2*m);
d2v_y:=-((C_d)*rho*Pi*(r^2)*(v_y)*sqrt((v_x)^2 +(v_y)^2))/(2*m)-g;


C[d] is the drag coefficient (about 0.35 for a baseball)

rho[air] is the density of air (about 1.2 kg/
r is the radius of the ball (about 0.037 m)

v is the vector velocity of the ball

Then if given that : 

Power hitters in baseball say they would much rather play in Coors Field in Denver than in sea-level stadiums because it is so much easier to hit home runs. The air pressure in Denver is about 10% lower than it is at sea level. The field dimensions at Coors Field are:

Left Field - 347 feet (106 m)
Left-Center - 390 feet (119 m)
Center Field - 415 feet (126 m)
Right-Center - 375 feet (114 m)
Right Field - 350 feet (107 m)

 1. Overlay two plots: one at sea level and one in Denver to show why power hitters prefer Coors field.

2. Find the initial magnitude of velocity, v0

needed to hit a home run to Right-Center, where v_x(0)=v0/sqrt(2) and v_y(0)=v0/sqrt(2)

I don't quite understand how to use the field dimensions for both 1 and 2 and am pretty clueless as to how to approach this question using the ordinary differential equations mentioned above.



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