Question

I must seem like a total newb, but I have zero experience with physics, and Professor Lewin seems to teach at a very advanced level. I think I understood most of the concepts he was trying to get across however, and now it is simply a matter of trying to put it into practice.

I am on Problem 1 on Challenge Set 1 for Dimensional Analysis (I know, I feel slow and dumb). I have isolated the variables, and provided the units for each, but now I am trying to derive the function. We are trying to find time, and I am modeling professor Lewin's methods here, so I think the time it takes for the

Answer 1

liquid to flow out is proportional to the density of the liquid, multiplied times the volume, and then I am trying to find the function that will limit the rate of the flow due to the function of the second hole at the bottom of the cylinder A2. I think that k=liquid means that K is the rate of flow out of the second hole, but I don't know the relationship with the rest of the function. Does it have an inverse or direct relationship with density and volume or is it more complicated? Thanks!

Answer 2

Hello

You better start from writing down the proportionality relationship between t and all present parameters.

The parameters present here are : ρ, A1, A2, h and g.
so the time that the liquid takes to flow out should be proportional to these parameters.
\[t \alpha ρ^{\alpha}.g^{\beta}.h^{\gamma}.A1^{\delta}.A2^{\epsilon}\]

And then write your equations .. and try to use any other equation to find out the remaining unknowns.