Velocity and resistance problem. diff Eq type

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SUMMARY

The discussion focuses on solving the differential equation representing a body moving with velocity V under resistance, expressed as dV/dT = -k*V^(3/2). The correct solution for V(t) is derived as V(t) = (4v.)/(k*t*sqrt(v.)+2)^2, where v. denotes the initial velocity v(subscript 0). Participants emphasized the importance of integrating the equation and verifying initial conditions to arrive at the solution. The discussion highlights the necessity of careful manipulation of constants and initial conditions in differential equations.

PREREQUISITES
  • Understanding of differential equations, specifically first-order equations.
  • Familiarity with integration techniques and initial value problems.
  • Knowledge of physical concepts related to velocity and resistance.
  • Proficiency in manipulating algebraic expressions and constants in equations.
NEXT STEPS
  • Study the method of integrating first-order differential equations.
  • Explore the application of initial conditions in solving differential equations.
  • Learn about the physical implications of resistance in motion, particularly in fluid dynamics.
  • Investigate other forms of resistance equations and their solutions in physics.
USEFUL FOR

Students and professionals in physics and engineering, particularly those dealing with motion dynamics and differential equations. This discussion is beneficial for anyone looking to deepen their understanding of resistance forces and their mathematical modeling.

jd1828
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A body moving with velocity V enounters a resistance in the form of dV/dT=-k*V^(3/2). Show that

V(t)=(4v.)/(k*t*sqrt(v.)+2)^2
v. is the same as v(subscript 0)


When i solve the differential equation i keep getting V(t)=4/(k*t-v')^2

I have no idea how to get from dv/dt to the given v(t)
 
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oh wow I would have never though to that!

since i figured it out on my own, you verify from v(t) that v(0)=v. solve the diff eq then set t=0 and set it = to v. solve for constant C sub back into equation and get the anwser.
 

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