Question

A solid glass sphere of radius R (m = 1.5) is silvered over one hemisphere as shown in figure. A point object is placed at a distance 2R from the pole of unsilvered part. Position of final image from centre of sphere is –

• A. At $\frac { \mathrm { R } } { 2 }$ towards object
• B. At towards pole of silvered side
• C. At centre of sphere
• D. At pole of silvered part

Answer 1

Answer: (D)

At pole of silvered part

Answer 2

For refraction

$\frac { 1.5 } { v _ { 1 } }$ – =

Ž v₁ =  i.e. parallel beam

For Reflection

= $\frac { 1 } { - \mathrm { R } / 2 }$

Ž v₂ = – R/2

For Final Refraction

$\frac { 1 } { \mathrm { v } _ { 3 } } - \frac { 1.5 } { - 3 \mathrm { R } / 2 }$ =

Ž v₃ = – 2R i.e. at pole of silvered part