fluid dynamics

In my studying I came across a different version of Poiseuille's Law than I'm used to seeing. While I am used to seeing it in this form: I just saw a problem easily solved by using the form below, which is showing a "resistance to flow" value 'R' rather than a flow rate 'Q': How can one of...

When you suddenly stand up after lying down for a while, your body may not compensate quickly enough for the pressure changes and you might feel dizzy for a moment.. If the gauge pressure of the blood at your heart is 13.3 kPa and your body doesn’t compensate, (a) what would the pressure be...