Light obliquely travel from glass to air , critical angle of glass is `42^@`.
What happens to the ray ofd light when the angle of incidence is `45^@` ? Explain the phenomenon ?

What is the critical angle of glass?

Light obliquely travel from glass to air , critical angle of glass is 42^@ . Angle of incidence is 42^@ find its refracted angle ?

Light obliquely travel from glass to air , critical angle of glass is 42^@ . What is mean by critical Angle ? In which phenomenon we observe the incident angle is 40^@ ? Explain the phenomenon ?