I'm having trouble with the 2nd part of this problem. By letter "d" I mean "partial," I wasn't able to preview latex, so I went without it.(adsbygoogle = window.adsbygoogle || []).push({});

x=x'+V*t' (V is a constant)

t=t'

f=f(x,t)

Part a

=====

Find df/dt' and df/dx'. I got the following:

df/dt'=df/dt+V*(df/dx)

df/dx'=df/dx

Am I correct?

Part b

=====

Consider substantial derivatives of density "g" and velocity "v" (which are also function of time and space), which are:

dg'/dt'+v'*(dg'/dx')

dv'/dt'+v'*(dv'/dx')

Show that substantial derivatives have the same form when transformed into the x,t coordinate system (g'=g, v'=v-V).

What I get is not of the same form:

dg/dt-V*(dg/dx)

dv/dt-V'*(dv/dx')

My problem is in the setup of this problem. How do I start?

Thanks

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# Homework Help: Galilean Transformation and Substantial Derivative

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