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प्रश्न
Which of the following can make a parallel beam of light when light from a point source is incident on it?
विकल्प
Concave mirror as well as convex lens
Convex mirror as well as concave lens
Two plane mirrors placed at 90° to each other
Concave mirror as well as concave lens
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उत्तर
Concave mirror as well as convex lens
Explanation -
When the point source is kept at the focus of the concave mirror and convex lens, the light rays after reflection and refraction respectively, will become parallel to the principal axis.
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