(Long Answer Question) A concave mirror is marketed as a “shaving mirror” because it…
PHYSICS · Multi-part · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction
Problem
(Long Answer Question)
A concave mirror is marketed as a “shaving mirror” because it can produce an erect, magnified image of the user.
Let the desired magnification be +2 (image twice the size of the object and erect).
Answer the following.
(i) Starting from the mirror–magnification relation, derive an expression connecting the object distance u and focal length f for which the magnification is +2.
(ii) If the mirror has focal length 15cm, calculate the precise object distance and image distance that satisfy the magnification requirement.
(iii) The same mirror is now used to project a real image on a screen kept 80cm in front of the mirror (on the reflecting side). Determine the corresponding object position that will produce this real image on the screen.