{"id":2205,"date":"2026-05-07T15:23:08","date_gmt":"2026-05-07T22:23:08","guid":{"rendered":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/?p=2205"},"modified":"2026-05-07T16:00:47","modified_gmt":"2026-05-07T23:00:47","slug":"optics-magic","status":"publish","type":"post","link":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/optics-magic\/","title":{"rendered":"Optics Magic"},"content":{"rendered":"

Overview<\/strong>: Refraction<\/a> and Persistence of Vision<\/a> are two optical phenomenon we can use to create “magic”<\/p>\r\n

Refraction is the bending or change in direction of light as it passes from one transparent medium to another (e.g., air to water or glass). This phenomenon occurs because light travels at different velocities in different materials. We can use refraction to create the illusion of an optics magic show.<\/p>\r\n

Persistence of vision\u00a0is the\u00a0optical illusion\u00a0that occurs when the\u00a0visual perception\u00a0of an object does not cease for some time after the\u00a0rays of light\u00a0from it have ceased to enter the\u00a0eye.<\/p>\r\n

Supplies<\/strong>: Magic trick 1: Small jar, water beads, small colored toy, water<\/p>\r\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Magic trick 2: Coffee mug, coin, water<\/p>\r\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Magic trick 3: Clear glass, pencil or pen, water<\/p>\r\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Magic trick 4: Screwgun, color wheel<\/p>\r\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Magic trick 5: Praxinoscope<\/p>\r\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Magic trip 6: Thaumatrope<\/p>\r\n

Objectives<\/strong>: Show how each magic trick deceives us into thinking one thing, but we see another. Understand how refraction and persistence of vision makes these magic tricks possible.<\/p>\r\n\r\n\r\n

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Setup<\/strong>:<\/p>\r\n\r\n\r\n\r\n

    \r\n
  • No particular setup necessary, other than putting out all the tricks on the table<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
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    \"\"\"\"<\/figure>\r\n<\/div>\r\n\r\n\r\n\r\n\r\n<\/div>\r\n\r\n\r\n\r\n

    How to run the demo:<\/strong><\/p>\r\n\r\n\r\n\r\n

      \r\n
    • Adjust the lasers until the spots overlap on the screen and form a yellow spot<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n

      \"\"\"\"\"\" \"\"<\/p>\r\n

      \r\n\r\n\r\n

      What’s Happening?<\/strong><\/p>\r\n\r\n\r\n\r\n

      This form of color mixing is called additive mixing, where the combination of primary colors (red, green, and blue) creates white light. When you combine two of the three primary colors you can create magenta, cyan and yellow. Take a red and green laser to combine their light together and make yellow spot. Note that this is different than subtractive mixing; we experience subtractive mixing with paint and inkjet printers, where the combination of primary colors (cyan, yellow, magenta) creates black paint.<\/p>\r\n\r\n\r\n\r\n

      <\/figure>\r\n\r\n\r\n
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      <\/figure>\r\n<\/div>\r\n\r\n\r\n\r\n
      \r\n
      <\/figure>\r\n<\/div>\r\n<\/div>\r\n\r\n\r\n\r\n

      Learn more:<\/strong> (external links)<\/p>","protected":false},"excerpt":{"rendered":"","protected":false},"author":130,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,2,8],"tags":[],"class_list":["post-2205","post","type-post","status-publish","format-standard","hentry","category-everyday-optics","category-optical-illusion","category-physical-optics"],"_links":{"self":[{"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/posts\/2205","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/users\/130"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/comments?post=2205"}],"version-history":[{"count":9,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/posts\/2205\/revisions"}],"predecessor-version":[{"id":2214,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/posts\/2205\/revisions\/2214"}],"wp:attachment":[{"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/media?parent=2205"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/categories?post=2205"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/oscoutreach\/wp-json\/wp\/v2\/tags?post=2205"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}