I am trying to solve the general equation for a body falling in drag so I can apply it to many objects. But Mathematica seems to have problems with having anything but numbers and your independent and dependent variables as an argument. So if I want to leave the mass, a constant with respect to the DE, unspecified (to be supplied at a later date), it can't handle it.(adsbygoogle = window.adsbygoogle || []).push({});

Here is my most recent attempt:

Y[t_, m_, A_] := y[t] /. DSolve [{-m 1/2 Cw \[Rho] A y'[t]^2 + m g == y''[t], y'[0] == 0, y[0] == h}, y[t], t]

The delayed assignment was my attempt to get around the coefficients not being supplied. If I try to use that, by say, doing BB[t] = Y[t, .145, Pi .0366^2], mathematica throws the error

Solve::inex: Solve was unable to solve the system with inexact coefficients or the system obtained by direct rationalization of inexact numbers present in the system. Since many of the methods used by Solve require exact input, providing Solve with an exact version of the system may help

I was also thinking of using Assume, but as far as I can tell, you can't assume with DSolve. I am new to Mathematica so it's also possible that there is a simple solution I am unaware of.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Mathematica's DSolve with unspecified constant parameters

**Physics Forums | Science Articles, Homework Help, Discussion**