Which of the following materials has maximum optical density?

$A$ child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size, and that of the legs smaller. What is the order of combinations for the magic mirror from the top?

How will you decide whether a given piece of glass is a convex lens,concave lens,or a plane glass plate?

When does Snell's law fail?

The image of an object formed by a plane mirror is due to which optical phenomenon?

The refractive index of dense flint glass is $1.65$ and for alcohol it is $1.36,$ with respect to air. What is the refractive index of dense flint glass with respect to alcohol?