Healthcare and medicine
The Heart

Blood pressure

  1. What is blood pressure?
  2. Learn how a stethoscope can help determine blood pressure
  3. Resistance in a tube
  4. Adding up resistance in series and in parallel
  5. Adding up resistance problem
  6. Flow and Perfusion
  7. Putting it all together: Pressure, flow, and resistance
  8. Blood pressure changes over time

Resistance in a tube Learn how the size of a tube (it's radius) is related to its resistance to something flowing through. Rishi is a pediatric infectious disease physician and works at Khan Academy.

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Resistance in a tube

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