question_answer

Which of the following correctly depicts reflections in case of plane mirrors inclined at \[40{}^\circ ?\]

A)             

B)

C)              

D)  

Correct Answer: A

Solution :

Using law of reflection, \[\because \angle i=\angle r={{90}^{o}}-{{50}^{o}}={{40}^{o}}\] So, \[\angle NCB={{40}^{o}}\] \[\angle BCA={{90}^{o}}-{{40}^{o}}={{50}^{o}}\] In \[\Delta ABC={{180}^{o}}-{{40}^{o}}-{{50}^{o}}={{90}^{o}}\]