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An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse is
Correct answer is '33'. Can you explain this answer?
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Verified Answer
An observer standing on the deck of a ship just sees the top of a ligh...
Therefore distance of observer from light house
d = d1 + d2
= 8.62 + 24.38
= 33 km
Most Upvoted Answer
An observer standing on the deck of a ship just sees the top of a ligh...
Given data:
Height of the lighthouse = 40 m
Height of observer's eye = 5 m
To find:
Distance of the observer from the lighthouse
Solution:
Let's assume that the observer is standing at point O and the top of the lighthouse is at point L. Let the distance between points O and L be 'd'.
Using trigonometry, we can form a right-angled triangle with O, L and the point where the observer is able to see the top of the lighthouse. Let this point be A.
From the triangle OLA, we have:
tanθ = (Height of the lighthouse - Height of observer's eye) / d
Substituting the values, we get:
tanθ = (40 - 5) / d
tanθ = 35 / d
We know that tanθ = perpendicular / base
Here, perpendicular = Height of the lighthouse - Height of observer's eye = 35 m
Base = distance between the observer and the lighthouse = d
Hence, we get:
d = 35 / tanθ
Using a scientific calculator, we get:
d ≈ 33 km (approx)
Therefore, the distance of the observer from the lighthouse is approximately 33 km.
Height of the lighthouse = 40 m
Height of observer's eye = 5 m
To find:
Distance of the observer from the lighthouse
Solution:
Let's assume that the observer is standing at point O and the top of the lighthouse is at point L. Let the distance between points O and L be 'd'.
Using trigonometry, we can form a right-angled triangle with O, L and the point where the observer is able to see the top of the lighthouse. Let this point be A.
From the triangle OLA, we have:
tanθ = (Height of the lighthouse - Height of observer's eye) / d
Substituting the values, we get:
tanθ = (40 - 5) / d
tanθ = 35 / d
We know that tanθ = perpendicular / base
Here, perpendicular = Height of the lighthouse - Height of observer's eye = 35 m
Base = distance between the observer and the lighthouse = d
Hence, we get:
d = 35 / tanθ
Using a scientific calculator, we get:
d ≈ 33 km (approx)
Therefore, the distance of the observer from the lighthouse is approximately 33 km.
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Community Answer
An observer standing on the deck of a ship just sees the top of a ligh...
D=3.854(h1^0.5+h2^0.5)
h1=40,h2=5
h1=40,h2=5
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An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer?
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An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer? for Civil Engineering (CE) 2024 is part of Civil Engineering (CE) preparation. The Question and answers have been prepared according to the Civil Engineering (CE) exam syllabus. Information about An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer? covers all topics & solutions for Civil Engineering (CE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer?.
An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer? for Civil Engineering (CE) 2024 is part of Civil Engineering (CE) preparation. The Question and answers have been prepared according to the Civil Engineering (CE) exam syllabus. Information about An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer? covers all topics & solutions for Civil Engineering (CE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40 m above the sea level and the height of the observer’s eye is 5 m above the sea level. The distance (in km, up to one decimal place) of the observer form the lighthouse isCorrect answer is '33'. Can you explain this answer?.
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