Desperately need help with a mechanics question involving ODEs

bs00184

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An object of mass m=1 is thrown in a uniform gravitational field g with some initial speed v at some angle theta. It is shaped however such that it experiences a frictional force proportional to its velocity: Ffriction = -kV,where k is simply a constant of proportionality.

Write down and solve the two differential equations describing the motion of the particle r(t) = x(t)X + y(t)Y. You may find the ansatz for the particular integral rPI(t)= (At)Y useful.




I have been trying to do this question and I have got an answer from this but I am unsure if it is correct because of the suggestion that (At)Y is the particular integral as I didn't get this. I am in desperate need for this question to be answered as there as a lot of follow up questions after this. I understand the forces acting on this particle, however I am expecting to get a second order ODE for my y direction but I am only getting a second order for my x direction which wouldn't make sense.
If anyone can help I will be very grateful!
Thank you!
 
An object of mass m=1 is thrown in a uniform gravitational field g with some initial speed v at some angle theta. It is shaped however such that it experiences a frictional force proportional to its velocity: Ffriction = -kV,where k is simply a constant of proportionality.

Write down and solve the two differential equations describing the motion of the particle r(t) = x(t)X + y(t)Y. You may find the ansatz for the particular integral rPI(t)= (At)Y useful.




I have been trying to do this question and I have got an answer from this but I am unsure if it is correct because of the suggestion that (At)Y is the particular integral as I didn't get this. I am in desperate need for this question to be answered as there as a lot of follow up questions after this. I understand the forces acting on this particle, however I am expecting to get a second order ODE for my y direction but I am only getting a second order for my x direction which wouldn't make sense.
If anyone can help I will be very grateful!
Thank you!
Please share your work (answer) with us - so that we know where to begin to help you.
 
Please share your work (answer) with us - so that we know where to begin to help you.

I don't have an issue with solving the ODE, but at this stage I don't feel it is correct because I am expecting to get the second order ODE for the y direction.
 

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