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A biconvex lens is cut in such a way that its equal two halves are (i) XOX. and (ii) YOY.axis respectively. If the focal length of original lens is fi f. is focal length in case (i) and fi in case (ii), then which of the following is true ? |
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Answer» f.=2f,f..=2f  `1/f=(mu-1)((1)/(R_1)-(1)/(R_2))` In this CASE, `R_1` and `R_2` doesn.t CHANGE. Hence, focal LENGTH of both is f. `therefore f.=f`  which is combination of two lenses of same focal length. `therefore 1/f=(1)/(f_1)+(1)/(f_2)`where `f_1=f_2=f..` `therefore 1/f=(1)/(f..)+(1)/(f..)=(2)/(f..)` `thereforef..=2f` |
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