Final answer:
The questions relate to the physics of light refraction, specifically how a light ray's direction and speed change as it moves between different media. Calculations involve using Snell's Law and concepts like total internal reflection.
Step-by-step explanation:
The topic pertains to the laws of refraction, specifically how a light ray behaves as it travels through different media with varying indices of refraction. The questions involve calculating the lateral shift of a light ray through a glass block, determining times for light to travel through optical fibres, finding the height and apparent depth of objects in water based on angles of incidence and refraction, and identifying substances by their refractive indices. Such phenomena are explained by considering the changes in light speed as it enters mediums with different optical densities.
For example, to calculate the lateral shift (d) of a light ray through a glass block, you would use Snell's Law, which relates the angle of incidence to the angle of refraction and the indices of refraction of the two media. This law also helps in calculating critical angles for total internal reflection and identifying substances by their refractive indices.