What is the solution for the laminar flow problem?

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SUMMARY

The laminar flow problem involves a barge being pulled by two horses in a viscous fluid, with a mass of 3000 kg and a net forward force of 300 Newtons. The maximum attainable speed of the barge is 2.5 m/s, leading to the calculation of the resistive coefficient, k, which is determined to be 120 N·s/m. The time taken to reach a speed of 1 m/s is calculated using the equation of motion derived from Newton's second law. Upon ceasing to pull, the barge's deceleration and drift distance are analyzed, revealing that it takes approximately 25 seconds to come to rest.

PREREQUISITES
  • Understanding of Newton's second law of motion
  • Familiarity with laminar flow dynamics
  • Knowledge of differential equations and integration techniques
  • Basic principles of kinematics
NEXT STEPS
  • Study the derivation of resistive coefficients in fluid dynamics
  • Learn about the application of Newton's second law in varying resistance scenarios
  • Explore the integration of motion equations for objects in viscous fluids
  • Investigate the effects of different fluid viscosities on motion and resistance
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Physics students, engineers, and anyone interested in fluid dynamics and motion analysis in viscous environments will benefit from this discussion.

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Problem:
Two horses pull a barge from rest in a canal filled with a viscous fluid that provides laminar resistance (FR = –kv). The two horses walk on each side of the canal so that their net force is applied exactly forward. The barge has a mass of 3000 kg and the donkeys pull forward with a constant net forward force of 300 Newtons.

a. If the maximum attainable speed by the barge is 2.5 m/s, what is the resistive coefficient, k (include units)?
b. How long does it take the barge to reach a speed of 1 m/s?

Once the barge reaches 2.5 m/s, at a certain time (call it t = 0) the horses instantaneously stop pulling, and the barge is allowed to drift forward.

c. How long does it take for the barge to slow to 1 m/s?
d. How far does the barge drift before coming to rest?
e. In principle, how long does it take for the barge to come to rest? Briefly explain.
f. Estimate how long it takes for the bar to be, for all practical purposes, at rest. Discuss how you decided on this estimate.

Equations:
F=-kv

Attempt at a solution:
I know how to do the integrations of the laminar flow F=-kv. Other than that I really don't know how to do this.
 
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Let's start with part a. Please set up Newton's second law, solve for v(t), and post your findings.
 

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