Brechner, Claude H., 1887- [from old catalog] · Boston, New York [etc.] Allyn and Bacon · leaf 105
shoWS a shadoW Cast b*VSource of Light. an object in front of light coming from a point source. The light travels out in all directions from point P, butthat which strikes the rectangle abed is shut off, thus makingthe space S without light, or a shadow. The shadow, then,is a pyramid with the top… … SHADOW FROM A LARGE SOURCE 95 shows the shadow cast by an object (0) with a large sourceof light (S). It will be seen that the space above be and below ad islighted by all of S. The space between ac and bd beyondthe object gets no light at all, and so is totally dark. Thisis called the umbra (U).…
Physics
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