Page 1 - X Ch-9 Appl of Trigo CBQ-Worksheet for flip book

SAI International School

Class : X

Mathematics

Competency Based Questions

Ch-9 Application of Trigonometry

1 The shadow of a tower is equal to its height at 10-45 a.m. The sun’s altitude is:
0
0
0
0
(a). 30 (b) 45 (c) 60 (d) 90
2 A ladder 15 m long just reaches the top of a vertical wall. If the ladder makes an angle of 60° with
the wall, then the height of the wall is:

3 The tops of two poles of heights 20 m and 14 m are connected by a wire. If the wire makes an angle
of 30° with the horizontal, then the length of the wire is:
(a) 8 m (b) 10 m (c) 12 m (d) 14 m
4 If two towers of heights h1 and h2 subtend angles of 60° and 30° respectively at the mid-point of
the line joining their feet, then h1 : h2 is:
(a) 1 : 2 (b) 1 : 3 (c) 2 : 1 (d) 3 : 1
5 A portion of a 60 m long tree is broken by tornado and the top struck up the ground making an
angle of 30° with the ground level. The height of the point where the tree is broken is equal to
(a) 30 m (b) 35 m (c) 40 m (d) 20 m
(A) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion
(A)
(B) Both assertion (A) and reason (R) are true and reason (R) is not the correct explanation of
assertion (A)
(C) Assertion (A) is true but reason(R) is false.
(D Assertion (A) is false but reason(R) is true.
6 Assertion(A) : The angle of elevation increases when the point of observation moves towards the
object.
Reason(R) : The angle of elevation increases when the point of observation moves away from the
object.
7 Assertion(A) : The angle of depression is the angle between the horizontal line and the observation
of the object from the horizontal line
Reason(R) : Angle of depression is always reflex angle

8 Assertion(A) : If the length of shadow of a vertical pole is equal to its height, then the angle of
elevation of the sun is 45˚
Reason(R) : According to Pythagoras theorem where h = hypotenuse, l = length and
b = base

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