Sentence Examples


  • The notions of the penumbra and umbra are important in considering eclipses (q.v.).
  • In the neighbourhood surrounding the penumbra the granules appear to be packed more closely, forming brilliant patches called faculae.
  • There will be a gradual increase of brightness in the penumbra from total darkness at the edge next the geometrical shadow to full illumination at the outer edge.
  • But if we place a body at a distance of a foot or two only from the arc, the shadow cast will have as much of penumbra as if the sun had been the source.
  • The penumbra remains the penumbra, but it is now darkest where before it was brightest, and vice versa.
 

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