Lighthouses Help
Thursday, November 1st, 2007lighthouses help
How tall does a lighthouse need to be to be visible to a vessel (25km out to sea)?
Given that the radius of the earth is 6370km.
I know how to do this with trigonometry, but I'm not supposed to use that in this question.
Help!
You can use the Pythagorean theorem. If you presume that at sea you can see the horizon at an angle of 0 degrees (which is normal to the radius of the earth in this point), then the tip of the lighthouse which is 25 km away is visible just. The triangle you need is represented with this three points: the center of the earth, the vessel, the tip of the lighthouse, or the following equation:
6370^2+25^2=(6370+h)^2
where h is the height of the lighthouse.
The result is h=49 m, plus something.
See, no trigonometry function.
Hope you got the same result with trigonometry.
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Alexandria: Ancient Treasure Vs. Modern Tourism Destination
Let's start with the fact that Alexandria is the "home town" for one of the 7 wonders of the Ancient World. I'm talking about the Alexandrian lighthouse. Even though this lighthouse is not fitting into the modern standards, it used to be great equipment back in time. They even believe that the lighthouse saved thousands of people.
Let's add to this the fact that 2 of the most popular ancient buildings are over here- Alexandrian Library and Greco-Roman Museum. The first one is hosting various manuscripts and books from all over the world and the fact that you can visit it is jus AWESOME. The Greco-Roman museum will help the tourists to learn more about the historical events and the culture of the ancient times.
We will also discover you the fact that soon you'll be able to witness not only the surface but also underwater treasures of Alexandria. There's a large amount of territory in Alexandrian Bay, where you'll be able to see the remains of various monuments and buildings. A group of architectures is planning to create an underwater museum. Here, the visitors will be able to come by the special equipments designed for the guest visit.
Except all of this, the authorities are making all of the necessary clean ups within the city. The city itself is rather cute, has various hotels and restaurants, where the guests can organize their unique rest.
All of this leads to the idea that soon we can say that Alexandria- the future capital of tourism.
About the Author
Molokini
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