Recent content by potto

Because its fixed volume, a brick submerged in water displaces a unique mass of water, being moving or not. When forced to move along a horizontal line, it offers different resistance (or drag) depending on the position in which it is forced to move. The first statement is correct and I agree...

Yes, there large body of research on this point, I can refer you to some papers. this kind of work refers as fish locomotion. Or swimming bodies studys. It is well established that the added mass must be considered.

I would not agree with you. Mass in physics and engineering is defined as the resistance to the acceleration (not to gravity specifically). And it happend that the added mass is affected by the gravity (put water on scale and you have a weight). In this case, this added mass resisting the...

That is the exact point I m trying to make. It not have to be circular. Any physical shape will be good. Image square body pushing the water. The water in front is pushed but in turn push the water a head of it. This continue until some water take the place of the body where it was before. The...

I read your link. I would sugget some changes to the text in the page if you would be interested. The accuracy of the page can be increased.

It is true that our body (brain) make us think in a certain ways. The question is whether there is a physical effect that actually we feel. I think that there is a strong effect which is the added mass. This effect happend is because we have to move the liquid around us (or accelerate it).

I take the point that was made by others below. The viscous forces related to the velocity. If the velocity is zero than there is no viscous forces. Yet the resisting force is very large which can be explain only the added mass.

Very good point, drag is related to velocity. I cannot agree more with this statement. And this point actually strengthen the argument for the added mass. Take this illustration, suppose you have zero velocity hence you have zero drag (viscosity effect). In the same time you have large...

Thank you for your reply. There are two phenomena that occur in the same time. One that you are talking about which buoyancy. Your weight in the water is smaller then in air. People conflating this effect with fact that move a hand for example you fill that is very hard to do and it harder...

``But, with our bodies, which are mostly water, the bouyancy effect cancels out the added mass effect. The body would have then an effective mass pretty much the same as that in air.'' How the buoyancy cancel the added mass? It is not clear to me. According the book ``Basics of Fluid...

I think that you have a point. This question bother me so I have research the web and I think that I found the solution. This phenomenon is physical and it based on the idea that when the air or water you move additional mass that move because you occupy volume. I found this explanation on...

I am searching for the common explanation why people believe it is so. Google and other places are suggesting that it related to gravity. However. the gravity (buoyancy) reduces our weight. The question: do we really heavier in water? If it is not the case, what makes us think that we are...

I would suggest that you check the "Basic of Fluid Mechanics" by Bar-Meir at www.potto.org with no contest the book contains the best chapters on several topics such as Static and integral equations/analysis and dimensional analysis. While you are there you should also grep the compressible...

You can get several book in fluid mechamics at www.potto.org for free.

we have the solution Recently this problem was solved. The governing equation leads to an integral equation which has an exact analytical solution. see here http://www.potto.org/downloadsFM.php in static chapter and some in the introduction. good luck!