Physics
The diagram below shows a light source P embedded in a rectangular glass block ABCD of critical angle 42°. Complete the path of the ray PQ till it emerges out of the block. [Write necessary angles.]
![The diagram below shows a light source P embedded in a rectangular glass block ABCD of critical angle 42°. Complete the path of the ray PQ till it emerges out of the block. [Write necessary angles.] ICSE 2019 Physics Solved Question Paper.](https://cdn1.knowledgeboat.com/img/abp10/5/icse-2019-physics-question-paper-solved-2e-1200x730.png)
![The diagram below shows a light source P embedded in a rectangular glass block ABCD of critical angle 42°. Complete the path of the ray PQ till it emerges out of the block. [Write necessary angles]. ICSE 2019 Physics Solved Question Paper.](https://cdn1.knowledgeboat.com/img/abp10/5/icse-2019-physics-question-paper-solved-2e-completed-diagram-1200x821.png)
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