Here you get the CBSE Class 10 Mathematics chapter 8, Introduction to Trigonometry and its Applications: NCERT Exemplar Problems and Solutions (Part-IIB). This part of the chapter includes solutions of Question Number 8 to 12 from Exercise 8.2 of NCERT Exemplar Problems for Class 10 Mathematics Chapter: Introduction to Trigonometry and its Applications. This exercise comprises only the Very Short Answer Type Questions framed from various important topics in the chapter. Each question is provided with a detailed solution.
NCERT Exemplar problems are a very good resource for preparing the critical questions like Higher Order Thinking Skill (HOTS) questions. All these questions are very important to prepare for CBSE Class 10 Mathematics Board Examination 2017-2018 as well as other competitive exams.
Find below the NCERT Exemplar problems and their solutions for Class 10 Mathematics Chapter, Introduction to Trigonometry and its Applications:
Very Short Answer Type Questions (Q. No. 8-12)
Write whether True or False and justify your answer.
Question. 8 If a man standing on a platform 3m above the surface of a lake observes a cloud and its reflection in the lake, then the angle of elevation of the cloud is equal to the angle of depression of its reflection.
Let the observer stands on point P on a platform 3m above the surface of a lake. Also, let C be the cloud and C’ be its reflection in lake. Again, let height of the cloud from the surface of the platform be h and q1 and q2 be the angle of elevation and angle of deptression respectively of the cloud.
Question. 11 The angle of elevation of the top of a tower is 30°. If the height of the tower is doubled, then the angle of elevation of its top will also be doubled.
Question. 12 If the height of a tower and the distance of the point of observation from its foot, both are increased by 10%, then the angle of elevation of its top remains unchanged.
Case II: On increasing height of a tower and the distance of the point of observation from its foot, by 10%, we have:
Hence, the angle of elevation of the tower top remains unchanged.