Q3 of 102 Page 130

By closing the eyes and gently pressing them with your palms, you may see some specks of brilliant light. How do you get this sensation while there is no light entering your eyes?

If we look at a bright object and then close our eyes, the sensation of light persists for a short period. This is known as persistence image or the after image. It lasts for one-tenth of a second. Therefore, by closing the eyes and gently pressing them with your palms, you see some specs of brilliant light.


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