CBSE Class 12-science Answered

Dear Student

Above critical angle there will be complete internal reflection

Q1)

If Ctitical angle =θ_c

Sin θ_c =  n₂/n1     Wheren₁ n₂    are more and les dense midium's refractive indeces respectively

In our case   n₁=1 (Air),    n₂    =1.33 (water)

Sin θ_c =  n₂/n1     =1/1.33   =0.752  ===> θ_c= 48.7⁰

So,   Radius of the illuminated region=   Pond Depth X Sin θ_c  = 0.752 h

 Q2)

when viewed normally  there is oil of length 10cm  and after that water if lenght 10 cm

Opticl path length =  length/ Refractive ingex =  10/1.4   +  10/1.33  = 14.66 cm

appt. depth of the tank when viewed normally =  14.66cm

Regards

Team

Topperlearning