ODE Methods for Physicists (related question)

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The discussion focuses on solving the ordinary differential equation (ODE) $$\frac{1}{v^3}\frac{dv}{dt}=-\frac{1}{2}\frac{dv^{-2}}{dt}$$ and requests a working guide for this equation. An integrating factor is suggested as a method for solving the ODE. Additionally, it is noted that aerodynamic force is related to the square of the velocity rather than the cube. The conversation emphasizes the need for clarity in the application of ODE methods in physics. Understanding these concepts is crucial for accurate modeling in dynamics.
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Homework Statement
A mass ๐‘š is accelerated by a time-varying force ๐›ผ ๐‘’๐‘ฅ๐‘(โˆ’๐›ฝ๐‘ก)๐‘ฃ3, where v is its velocity. It also experiences a resistive force ๐œ‚๐‘ฃ, where ๐œ‚ is a constant, owing to its motion through the air. The equation of motion of the mass is therefore
๐‘š๐‘‘๐‘ฃ/๐‘‘๐‘ก= ๐›ผ ๐‘’๐‘ฅ๐‘(โˆ’๐›ฝ๐‘ก)๐‘ฃ^3 โˆ’ ๐œ‚๐‘ฃ.
Find an expression for the velocity v of the mass as a function of time, given that it has an initial velocity ๐‘ฃ0
Relevant Equations
๐‘š๐‘‘๐‘ฃ/๐‘‘๐‘ก= ๐›ผ ๐‘’๐‘ฅ๐‘(โˆ’๐›ฝ๐‘ก)๐‘ฃ^3 โˆ’ ๐œ‚๐‘ฃ.
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$$\frac{1}{v^3}\frac{dv}{dt}=-\frac{1}{2}\frac{dv^{-2}}{dt}$$
 
Please can i get a working guide to this answer
Chestermiller said:
$$\frac{1}{v^3}\frac{dv}{dt}=-\frac{1}{2}\frac{dv^{-2}}{dt}$$
Please can i get a working guide to this answer?
 
profgabs05 said:
Please can i get a working guide to this answer
Please can i get a working guide to this answer?
$$\frac{dx^n}{dx}=nx^{n-1}$$
 
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My attempt: Initial total M.E = PE of hanging part + PE of part of chain in the tube. I've considered the table as to be at zero of PE. PE of hanging part = ##\frac{1}{2} \frac{m}{l}gh^{2}##. PE of part in the tube = ##\frac{m}{l}(l - h)gh##. Final ME = ##\frac{1}{2}\frac{m}{l}gh^{2}## + ##\frac{1}{2}\frac{m}{l}hv^{2}##. Since Initial ME = Final ME. Therefore, ##\frac{1}{2}\frac{m}{l}hv^{2}## = ##\frac{m}{l}(l-h)gh##. Solving this gives: ## v = \sqrt{2g(l-h)}##. But the answer in the book...