Question

You are given water , diamond and glass In which of these
does the light travel fastest? why?​

Answer 1

Since water has lowest refractive index, so light travels fastest in this optically rarer medium than kerosene and turpentine oil. A concave lens of focal length 15 cm forms an image 10 cm from the lens.

Answer 2

Answer:

Since water has lowest refractive index, so light travels fastest in this optically rarer medium than kerosene and turpentine oil.