
The relationship between the object distance \( u \), the image distance \( v \), and the radius of curvature \( R \) is given by the lens formula for spherical boundaries:
\( \frac{n_1}{v} - \frac{n_2}{u} = \frac{n_2 - n_1}{R} \)
Substituting the given values for \( n_1 \), \( n_2 \), and \( R \), we calculate the image distance \( v = 18 \, \text{cm} \) in the denser medium.
This means that the image is formed closer to the spherical surface in the denser medium.
If \( r \) and \( r' \) denote the angles inside the prism having angle of prism \( 50^\circ \), considering that during the interval of time from \( t = 0 \) to \( t = T \), \( r \) varies with time as \( r = 10^\circ + t^2 \). During this time \( r' \) will vary with time as 