Coloured light interference patterns on a plastic ruler & shallow dish (manufactured by an injection moulding process), used to illustrate the princip

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Coloured light interference patterns on a plastic ruler & shallow dish (manufactured by an injection moulding process), used to illustrate the principal of photo-elasticity as applied to stress distribution in objects under complex systems of loading. The object is photographed using cross polarised white light; the pattern of colours provides an isochromatic contour map of stress conditions throughout the object (isochromatic areas have the same colour & indicate similar conditions of stress). Transparent plastic models with stress loads proportional to real objects are made to determine stress distributions.

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Size: 4869px × 3245px
Photo credit: © SHEILA TERRY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: autumn, biological, biology, botanical, botany, cinerea, dispersal, fruits, grey, laden, multiple, nature, october, parts, plant, reproduction, reproductive, salix, sallow, seeds, soft, structures, tree, white, willow, wind