Physics
In a science exhibition, boys of a Secondary school made two types of periscopes. In one of the periscopes, ordinary glass was used as the reflecting material, while in the other, a prism was used. When Anushka put her eyes on the eyepiece of the periscope, she saw that the image formed in one of the periscopes was quite bright, while in the other, it was a little blurred.
(a) In which of the two periscopes, mirror or prism, Anushka saw the image brighter?
(b) Why is one of the images brighter than the other?
Refraction Plane Surfaces
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Answer
(a) Image is brighter in the prism periscope.
(b) This is due to the phenomenon of total internal reflection of light. During TIR, there is no absorption of light energy by the prism.
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