## Competency Based Questions of Maths for Class 10 Chapter 9 Some Applications of Trigonometry

Competency Based Questions are new type of questions asked in CBSE Board exam for class 10. Practising the following Competency Based Questions will help the students in facing Board Questions.

Hint:Identify line of sight in order to determine angle of elevation and angle of depression.

**Question.1.** Consider the figure shown. If \angleLJM is the angle of depression, what is the line of sight in the figure shown?

(a) JM

(b) JL

(c) JK

(d) KL

**Answer.** (b) JL

**Question.2.** Observe the figure below. If AR is line of sight, which of these angles represents the angle of elevation?

(a) \angleARC

(b) \angleRAP

(c) \angleACR

(d) \angleRAC

**Answer.** (a) \angleARC

Hint:Apply trigonometric ratios (of specific angles) in order to determine heights and distances of the objects.

**Question.3.** The angles of elevation of two cars, from the car to the top of a building are 45° and 30°. If the cars are on the same side of the building and are 50 m apart, what is the height of the building?

(a) 25( \sqrt{3}-1) m

(b) 25( \sqrt{3}+1) m

(c) 50( \sqrt{3}-1) m

(d) 50( \sqrt{3}+1) m

**Answer.** (b) 25( \sqrt{3}+1) m

**Question.4.** From the top of a 42 m high light house, the angles of depression of two ships that are in a straight line are 60° and 45° respectively. What is the distance between the two ships? (Use \sqrt{3} = 1.73)

(a) 17.8 m

(b) 24.2 m

(c) 32.39 m

(d) 66.28 m

**Answer.** (a) 17.8 m