Practice question

**Spherical mirror reflection** follows law θ_i = θ_r, focal length f = R/2, concave R negative, convex positive. Object beyond center C (u > 2f) forms image between F and C diminished, at C same size, between C and F magnified, beyond F forms at infinity, illustrating mirror equation. Shift = t ( 1 - (1/n) ) . t = 7.5 cm , n = 1.5 . Shift = 7.5 ( 1 - (1/1.5) ) = 7.5 ( 1 - (2/3) ) = 7.5 × (1/3) = 2.5 cm . Substituting values gives 2.5 cm, which matches expected image position and magnification from mirror/lens formula