Pre Lab 7¶

Here are some help for Pre lab 7!

Part 1: Find \(m\)¶

\[\rho = \frac{m}{V}\]

Now that you have \(\rho\) (density) and \(m\) (mass) in the equation, what about \(V\), the volume? Let’s look at the figure below:

Fig. 29 Visualization of fluid container¶

So, do you remember how to the find the volume, given cross-section area function (the same at all height) and height?

Caution

That figure does not tell whether the cross-section is circular. So, do not assume so. Please use the generic term \(A_b\) for area.

\(w\) is the term to indicate weight/gravitational force acting on a given fluid surface in this case.
At this point, you should know how to find it!
Start by asking yourself what is pressure?

Pressure is the force per unit area.

If you understand, you will think about this formula involing pressure difference:

\[\Delta{P} = \frac{F}{A_b}\]

Now, ask yourself what is \(F\) in this case? In the concept of fluid, the agent that exerts a force on a fluid cross-section at a certain height is all parts of fluid above that height right?
Then, what does that force equal to? Hopefully, it is clear.

Caution

For all questions above, make sure to give the equation in required terms from the question.