diff options
Diffstat (limited to 'source/know/concept/material-derivative')
-rw-r--r-- | source/know/concept/material-derivative/index.md | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/source/know/concept/material-derivative/index.md b/source/know/concept/material-derivative/index.md index 93e8ad0..7225053 100644 --- a/source/know/concept/material-derivative/index.md +++ b/source/know/concept/material-derivative/index.md @@ -16,9 +16,9 @@ e.g. the temperature or pressure, represented by a scalar field $$f(\va{r}, t)$$. If the fluid is static, the evolution of $$f$$ is simply $$\ipdv{f}{t}$$, -since each point of the fluid is motionless. +since each point is motionless. However, if the fluid is moving, we have a problem: -the fluid molecules at position $$\va{r} = \va{r}_0$$ are not necessarily +the fluid molecules at position $$\va{r} = \va{r}_0$$ are not the same ones at time $$t = t_0$$ and $$t = t_1$$. Those molecules take $$f$$ with them as they move, so we need to account for this transport somehow. |