Kinetic energy transfer from shockwave to secondary body

Click For Summary

Homework Help Overview

The discussion revolves around the transfer of kinetic energy from a shockwave to a secondary body, exploring the underlying physics concepts such as pressure, force, and dimensional analysis. Participants are attempting to understand how these factors interact in the context of shockwave dynamics.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants are considering the relationship between pressure, force, and distance to calculate work done by the shockwave. There are inquiries about the effects of medium density on shockwave behavior and the application of dimensional analysis to relate pressure, density, distance, and velocity.

Discussion Status

The discussion is ongoing, with participants expressing confusion and seeking clarification on dimensional analysis. Some have proposed methods to combine physical quantities to derive velocity, while others are questioning the validity of their approaches. There is no explicit consensus yet, but several lines of reasoning are being explored.

Contextual Notes

Participants have noted a lack of familiarity with dimensional analysis, which is influencing their ability to engage with the problem effectively. There is also mention of potential complexities arising from the transition between different media densities.

KataruZ98
Messages
27
Reaction score
3
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.
 
Physics news on Phys.org
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?
 
  • Like
Likes   Reactions: KataruZ98
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?
 
  • Like
Likes   Reactions: member 731016 and KataruZ98
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.
 
Last edited by a moderator:
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.
 
  • Like
Likes   Reactions: KataruZ98

Similar threads

Replies
23
Views
2K
  • · Replies 8 ·
Replies
8
Views
1K
Replies
1
Views
1K
Replies
2
Views
2K
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
Replies
17
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K