Related Experiment Video

Updated: Sep 21, 2026

Echo Particle Image Velocimetry
16:31

Echo Particle Image Velocimetry

Published on: December 27, 2012

The Shot Heard Round the World: A Reflection on Emerson's "Concord Hymn" and the United States Semiquincentennial

James B Young1, Justin C Cordova2,3

  • 1Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio, US.

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In a beam of charged particles created by a heated cathode, the particles move at different speeds. However, many applications need a beam with uniform particle speeds. An arrangement known as a velocity selector uses electric and magnetic fields to pick particles with a particular speed from the beam.
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An ellipse is a fundamental conic section defined by the constant sum of distances from any point on its curve to two fixed points, known as the foci. This geometric property can be physically demonstrated using a pencil, string, and two pins. By anchoring the string at both ends and maintaining it taut with a pencil, one can trace the outline of an ellipse.The shape and extent of the ellipse are determined by its eccentricity, e, defined as the ratio of the distance between the center and a...