The angle of elevation of a cloud from a point 60 m above the surface of the water of a lake
is 300
and the angle of depression of its shadow from the same point in water of lake is 600
.
Find the height of the cloud from the surface of water.
Answers
hope it will help u
Answer:
The Height of the cloud is 120 meters.
Step-by-step explanation:
After constructing the figure of the following case we get to know that:
AB = 60 meters
Let us assume that C is the point of cloud.
The Length CF is the Height of cloud from the surface of water.
We can equate it as CF = h m
We consider two triangles Triangle ABC and Triangle BED. They contain right angles.
EF = AB = 60 m (Opposite Sides Of A Rectangle)
Now, we consider Triangle BEC:
Tan B = Opposite / Adjacent side = CE / BE
Tan 30 = CE / BE
Substituting the values in the equation:
1/√3 = h - 60 / BE
By cross multiplying we get:
BE = √3(h - 60) -----------------(Equation 1)
Now, we consider right triangle BED:
Tan B = Opposite / Adjacent
Tan 60 = ED / BE
Substituting values in the equation:
√3 = h + 60 / BE
Substituting Equation 1 in the place of BE:
√3 = h + 60 / √3(h - 60)
Cross multiplying we get:
√3 * √3(h - 60) = h + 60
Simplifying,
3 (h - 60) = h + 60
3h - 180 = h + 60
3h - h = 60 + 180
2h = 240
h = 240 / 2 = 120 meters
Therefore, the Height of the cloud is 120 meters.