Question

A spherical mirror is polished on both sides, when convex side is used for reflection the magnification for an object is found to be $\frac { 1 } { 2 }$.The magnification when its concave surface is used for reflection (assuming object at same distance) :

• A. – $\frac { 1 } { 2 }$
• B. $\frac { 1 } { 2 }$
• C. –2
• D. None of these

Answer 1

Answer: (D)

None of these

Answer 2

For convex,

u = –x

m = +$\frac { 1 } { 2 }$ Ž v = – 4m = $\frac { x } { 2 }$

$\frac { 1 } { \mathrm { v } }$ + $\frac { 1 } { \mathrm { u } }$ = $\frac { 1 } { \mathrm { f } }$

–$\frac { 2 } { x }$ =

x = f

For concave, if u = –f

v = , m = 