Kinetic energy transfer from shockwave to secondary body

AI Thread Summary
The discussion focuses on calculating the work done by a shockwave on a secondary body, considering factors like pressure, force, density, distance, and velocity. Participants emphasize the importance of dimensional analysis to relate these variables, questioning how to combine them correctly to derive velocity. The conversation highlights the need to express velocity in terms of pressure, density, and distance using MLT notation. A method is proposed to set up equations based on dimensional analysis to solve for unknowns. Overall, the thread illustrates the complexities of kinetic energy transfer and the mathematical relationships involved.
KataruZ98
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Homework Statement
I have an object A possessing a known mass of 10kg and density of 1,000kg/m^3 exposed to a shockwave in a way the latter impacts A over an area of one square meter at a right angle. The pressure of the shockwave at the point of contact is 10PSI.
Relevant Equations
Kinetic energy transferred by the shockwave to body A
I would guess that by multiplying the pressure exerted by the shockwave on the body, and then the resulting force - here ~69 Newtons - per the distance the shockwave passed through when traversing body A, I could get the work done but I’m not sure if it’s that easy and whether or not I should consider the shockwave accelerating when passing from a less dense to denser medium.
 
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Thinking of it per unit area (doubling the area should yield the same velocity gain) we have a pressure, a density, a distance and a velocity. What does dimensional analysis say?
 
Hm, I’m kinda lost honestly. Unfortunately I’m not well versed.
 
KataruZ98 said:
Hm, I’m kinda lost honestly. Unfortunately I’m not well versed.
Are you unfamiliar with dimensional analysis? Look it up.
It uses M for mass, L for length, T for time,…
Pressure is ML-1T-2
Density ML-3
Distance L
Velocity LT-1
How can you combine the first three, raising each to some power and multiplying the terms together, to make the last?
 
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haruspex said:
Are you unfamiliar with dimensional analysis? Look it up.
It uses M for mass, L for length, T for time,…
Pressure is ML-1T-2
Density ML-3
Distance L
Velocity LT-1
How can you combine the first three, raising each to some power and multiplying the terms together, to make the last?
Well I would say I should divide density by the product of pressure and distance - though this leaves a T-2 as denominator.
 
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KataruZ98 said:
Well I would say I should divide density by the product of pressure and distance - though this leaves a T-2 as denominator.
Then that cannot be the answer.
The method is to let the answer be of the form velocity=pressure adensitybdistancec. In MLT notation that becomes ##LT^{-1}=(ML^{-1}T^{-2})^a(ML^{-3})^bL^c##.
Three equations, three unknowns.
 
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