Get the CBSE Class 10th Mathematics, Some Applications of Trigonometry: Important Questions & Preparation Tips. This will help with a precise description of the whole chapter along with a gist of each topic covered in the chapter. The Questions mentioned are exclusively topic oriented and are famous for its repetition in many Board papers. Consider the below mentioned points and questions at the time of preparation.
- Line of Sight: it is the line drawn from the eye of an observer to the point in the object viewed by the observer.
- Angle of elevation: It is the angle formed by the line of sight with the horizontal when the point being viewed is above the horizontal level. In the above figure, an observer at point C makes the angle of elevation when he looks upwards.
- Angle of depression: It is the angle formed by the line of sight with the horizontal when the point being viewed is below the horizontal level. In the above figure, an observer at point A makes the angle of depression when he looks downwards.
- What is the length of a string tied to a kite, flying at a height of 100 m and at an angle of elevation 30o? (1 mark)
- The angle of elevation of the top of the tower 100 m high is 60o with the horizontal. Find the distance of the observer from the foot of the tower. (2 mark)
- The angles of depression of two ships from the top of a lighthouse are 45o and 30o towards east. If the ships are 200 m apart, find the height of the lighthouse. (3 mark)
- A bridge across a river makes an angle of 45o to the river bank. If the length of the bridge across the river is 150 m, what is the width of the river? (3 mark)
- The angles of elevation of the top of a tower from two points at a distance of ‘a’ and ‘b’ from the base and on the same straight line with it are complimentary. Prove that the height of the tower is √ab. (4 mark)
- Two poles of equal heights are standing opposite to each other on either side of a road, which is 100 m wide. From a point between them on the road, the angles of elevation of their tops are 30o and 60o. Find the position of the point and also the height of the poles. (4 mark)