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I am having trouble numerically integrating a function using Maple 10. Here is a bit of background on the problem:

This problem is asking for two plots, one of the velocity of a sounding rocket with respect to time, and the other being the height of the sounding rocket with respect to time. Gravity and drag act on this rocket.

I have the following equations:

density as a function of altitude

drag coefficient as a function of mach number

mach number as a function of velocity

drag as a function of drag coefficient

thrust as a function of mass flowrate and exhaust velocity

mass as a function of time

This problem asks to create these plots for various values of mass flowrate that I am supposed to set myself (2 kg/s, 2.1 kg/s, 2.2...etc).

The known constants that I have are the following:

specific impulse

exhaust velocity

initial mass

initial velocity

initial height

initial density

After inputting everything into maple, I come up with this differential equation:

sys1 := [diff(v(t),t) = (thrust-drag-mass*9.81)/mass, diff(y(t),t) = v(t)];

I am not great with maple, so I am not sure if this is even the correct syntax.

In my attempt to solve the differential equation, I tried this command:

sol1 := dsolve(sys1, numeric, v(0)=0, y(0)=0);

Unfortunately, this gives me the following error:

Error, (in dsolve/numeric/type_check) insufficient initial/boundary value information for procedure defined problem

Any suggestions as to what may be causing the problem here? If necessary, I can post my entire maple file if more detail is needed. Thanks in advance.

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# Homework Help: Problem with numerical integration

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