Stuck with a problem from a take home test

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The discussion focuses on calculating the dissipating speed of kinetic and potential energy for a body free-falling into a viscous fluid. The potential energy is defined as mgh, while kinetic energy is expressed as (1/2)mv². It is noted that without numerical values, the calculation cannot proceed effectively. The term "dissipating speed" refers to the rate at which the total energy decreases due to the viscous fluid's resistance. Additionally, considerations regarding aerodynamic drag and terminal velocity, including the relevant Reynolds Number, are raised as important factors in the analysis.
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A body free fall into a viscous fluid. Calculate the dissipating speed of kinetic and potential energy during this motion into the fluid. ( suppose Yo initial height)
 
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Well, you can't do that if you are given no numerical values! What are you given? The potential energy is, of course, mgh where h is the height of the body. kinetic energy is (1/2)mv2. If there were no dissipation (no viscous fluid) the sum of those (total energy) would be constant. I presume that the "dissapating speed" is the rate at which that sum is decreasing.
 
joselyn said:
A body free fall into a viscous fluid. Calculate the dissipating speed of kinetic and potential energy during this motion into the fluid. ( suppose Yo initial height)
For instance, are you concerned with Aerodynamic Drag ("air resistance") and/or Terminal Velocity?? If so, what Reynold's Number range are you considering??
 
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