a. What is the focal length of the lens used in sunglasses?
b. The following figures show the path of light rays through three lenses marked $L_1, L_2$, and $L_3$ and their focal points $F_1, F_2$, and $F_3$, respectively. Identify the nature of lenses.
b. The following figures show the path of light rays through three lenses marked $L_1, L_2$, and $L_3$ and their focal points $F_1, F_2$, and $F_3$, respectively. Identify the nature of lenses.
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a. The focal length of a Sunglass lens is theoretically infinite. It is because the radii of curvatures of the front and back surfaces are equal.
b. Lens $L_1: f_1$
Lens $L_2: f_2$
Lens $L _3: f _3$
onvex lens because concave lens can never form virtual and magnified image of an object and convex lens form such image only when the object is placed between the optical centre and principle focus of the convex lens.
b. Lens $L_1: f_1$
Lens $L_2: f_2$
Lens $L _3: f _3$
onvex lens because concave lens can never form virtual and magnified image of an object and convex lens form such image only when the object is placed between the optical centre and principle focus of the convex lens.
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