Physics

The above diagram shows a glass prism of a critical angle 42°.
(a) Redraw the diagram and complete the path of the light ray PQ till it emerges out of the prism.
(b) Also, calculate the net angle of deviation of the ray PQ when it emerges from the prism.
Answer
(a) Below diagram shows the completed path of light ray PQ till it emerges out of the prism:

(b) In △APX
∠A = 48° and ∠APX = 90°
So,
∠AXP = 180° - (48° + 90°) = 42°
∠PXN = 90° - 42° = 48°
∠PXN = ∠XYB = 48° (∵ Corresponding angles)
Angle of deviation of the ray PQ = ∠ D = 180°- 48° = 132°
Related Questions
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(b) Plot on the graph,
i. The daughter element after the emission of beta radiation by the element ‘C’.
ii. The daughter element, as indicated in the previous answer, if it undergoes alpha decay.
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(c) Voltmeter reading.
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(a) Demonstrate, using mathematical calculations, that the path followed by student 1 is devoid of friction.
(b) Does the situation involving student 2 exhibit a breach of the law of conservation of energy?