Khan Academy: Stellar Distance Using Parallax

Gain an understanding of Stellar Distance Using Parallax in this in depth video. [11:40]

Sal Khan explains how to use parallax to figure out the distance of close stars. [9:26]

This explanation is a follow-up to a video on stellar parallax that answers a question about angles. [2:21]

Explains the concept of parallax and what it is in the context of nearby stars. [7:21]

Understanding why distance is area under velocity-time line. [9:25]

Does the distance between the copper and zinc electrodes matter? What happens to the deflection when we hold them close vs. far apart? Watch this visual demonstration to answer these questions. [1:05]

In this video, learn how to solve an elastic collision problem to find the final velocities using the shortcut approach. [10:19]

Learn how to help prevent tuberculosis by using the "4I's" model: Intensive Case Findings, Isoniazid, Isolation, and Immunization.

Figure out how all of those physiology terms - end-systolic, end-diastolic, pulse pressure, stroke volume, and ejection fraction - can be easily understood using the pressure-volume loop. Rishi is a pediatric infectious disease physician...

Watch how the fetal heart allows blood to simply bypass the lungs altogether using the Foramen Ovale and the Ductus Arteriosus! Rishi is a pediatric infectious disease physician and works at Khan Academy.