What should be the refractive index of a completely transparent medium for it to be invisible in vacuum ?

Question

What should be the refractive index of a completely transparent medium for it to be invisible in vacuum ? (A) Less than 1 (B) 1 (C) Greater than 1 (D) The medium cannot be invisible, whatever the value of refractive index.

Tardigrade Admin · Accepted Answer

In such a case optical behaviour of medium will be same as that of vacuum

Q. What should be the refractive index of a completely transparent medium for it to be invisible in vacuum ?

Less than 1

1

Greater than 1

The medium cannot be invisible, whatever the value of refractive index.

In such a case optical behaviour of medium will be same as that of vacuum