Trajectory of projectile with considerable drag

AI Thread Summary
The discussion focuses on solving the trajectory of a projectile with drag proportional to v^2, leading to a set of coupled differential equations. The equations describe the motion in terms of velocity, angle, and position, with initial conditions provided. Participants emphasize the importance of choosing a consistent coordinate system for solving the equations. There is a request for assistance in solving the mathematical aspects of the problem, despite previous attempts to find solutions. The conversation highlights the complexity of the equations and the need for guidance in tackling such differential equations.
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Facing some horrible mathematical situation while solving to find equation of trajectory of projectile when drag is proportional to v^2.
my equations where i end up with are as follow:
equation 1:
mdv/dt=(-kv^2)+(-mgsinγ);
equation 2:
(-mv)dγ/dt=mgcosγ;
equation 3:
dx/dt=vcosγ;
equation 4:
dy/dt=vsiny;
where:
v is velocity of particle at instance when it makes an angle γ with horizontal plane.
Initial condition is known and assume it to be u at an angle α.
please assist me in solving this.
 
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(1) ##m\dot v = -kv^2-mg\sin\gamma##
(2) ##-mv\dot \gamma = mg\cos\gamma##
(3) ## \dot x = v\cos\gamma##
(4) ## \dot y = v\sin\gamma##

Whence ##v(0)=u## and ##\gamma(0)=\alpha##

Do you want the trajectory: (x(t),y(t))?

Have you ever tried to solve systems of differential equations before?
(i.e. what is the level of education help should be aimed at?)

Have you seen:
http://users.df.uba.ar/sgil/physics_paper_doc/papers_phys/mechan/air0.pdf

You seem to be trying to use cartesian and some sort of polar coordinates at the same time - it is best practice to pick just one coordinate system and stick to it.
 
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Nugatory said:
This problem has come up before. Try this thread: https://www.physicsforums.com/showthread.php?t=712807


But I have already arrived at those set of coupled equations I want to know the way to solve it.
Assist me in solving mathematical part of the problem.
 
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