Question

what is the meaning of critical angle

Answer 1

It is the value of angle of incident for which angle of reflection is 90°

Hope this answer will help you.
My sister.

Answer 2

Hloo dear....

The critical angle is an angle beyond the rays of light passing through the denser medium to the surface of the less denser medium which would be totally reflected...

the angle of incidence provides an angle of refraction of 90-degree


Hope it helps
@zoyna