Mechanics Vibrations Homework: Piston Displacement & Time Calculation

AI Thread Summary
The discussion focuses on calculating the maximum displacement and time for a piston engaging with a spring and damper system. The piston has a mass of 4.53 kg and travels at 15.24 m/s, while the spring has a stiffness of 350 N/cm and the damper has a coefficient of 1.75 N.s/cm. The maximum displacement is calculated to be 128.6 mm, with a time to reach this displacement of 0.0157 seconds. The solution involves integrating the damping equation and applying initial conditions to find the maximum displacement when the velocity is zero. The conversation emphasizes the mathematical nature of the problem, indicating a focus on analytical solutions rather than purely physical interpretations.
tom l
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Homework Statement


A piston of mass 4.53(kg) is traveling in a tube with a velocity of 15.24(m/s). It engages a spring of stiffness 350 (N/cm) and a damper with a coefficient of 1.75 (N.s/cm)

What is the maximum displacement of the piston and how long does it take to reach this point?

Homework Equations


F= -kx
where
x is the displacement vector - the distance and direction in which the spring is deformed
F is the resulting force vector - the magnitude and direction of the restoring force the spring exerts
k is the spring constant or force constant of the spring.

velocity=displacement/time

Damping : http://en.wikipedia.org/wiki/Damping

The Attempt at a Solution


I have the solutions, Max. Displacement = 128.6(mm), Time Taken = 0.0157(s). I am stuggling to find a link between the known data and the displacement. Hope you can help
 
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Integrate the wikipedia equation with the conditions x(0)=0, v(0)=15.24 (cauchy problem); the system is underdamped, you will find a solution like exponential*sin, for the maximum displacement set the condition v(t)=0, i found it at t=0.01572s, if you want further help i can give you the analytic solution but I'm not good at Latex, it's more like a math exercise than a physic's one
 
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