A Hair Dresser Stands With Her Nose 20 Cm In Front Of A Plane Mirror For What Distance Must She Focus Her Eyes In Order To See Her Nose In The Mirror?

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A hair dresser stands with her nose 20 cm in front of a plane mirror for what distance must she focus her eyes in order to see her nose in the mirror?


Correct option is

40 cm




Distance from mirror = 20 × 2 = 40 cm.



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