Rabu, 12 Maret 2008

Bagaimana Terjadinya Geyser...

Geysers are a type of hot spring that erupt periodically, ejecting a column of hot water and steams into the air. Their emergence needs a combination of factors (water, heat and fortuitous plumbing) that exists in only a few places on Earth, and so they are fairly rare phenomena. There are about 1,000 worldwide. A geyser is like a volcano, having a cone and a small crater (called basin or reservoir), as it is refilled with hot water after each jet. The crater is connected to a canal which can be several meters wide. Hot water under pressure circulates through this canal coming from the inner crust of the Earth.

Geyser water can come from rainfall and snowfall penetrating through the cracks to volcanic rocks but it could also result from the condensation of the vapors produced by the magma. The hot temperature of the water is due in all cases to molten magma located a great depths. The solid deposits forming the cone are called geyserite.

1.Perhaps the most amazing thing in Yellowstone National Park is represented by these hot artesian springs, the geysers. This is the largest geyser field in the world! Yellowstone has about 500 geysers: half of all the geysers in the world! And 300 are really spectacular. The most famous are the Old Faithful, with extremely precise eruptions; the Giant Geyser, the largest in the world (it pushes water up to 61 m/203 ft, with a temperature of 94.8o C); the Lone Star Geyser, the Norris Geyser and others.

2.The second largest geyser field in the world, found in Kamchatka (Russia) is much smaller than that of Yellowstone: Dolina Geiserov ("Valley of Geysers"). This is the only place on continental Eurasia where geysers are encountered. In Kamchatka geyser field there are 34 big jets (20 m or 66 ft tall for 5-10 minutes) and 200 smaller thermal springs (jetting to 2 m (6.6 ft)) in a 2.7-square-mi (7-square-km) area. The water of this geysers has a temperature of 80o C.

The famous valley, part of the Kronotsky Nature Preserve, was buried, on June 3, after an entire mountainside collapsed. It has literally disappeared in a minute. If the river blockage is not broken, the valley could turn into a large heated lake.

Tourists visiting the uninhabited valley were lucky: a group of 19 barely escaped alive from the disaster, as the debris stopped less than 3 ft (1 m) from their helicopter and the buildings they were housed in.

Geyser River, which ran freely through the valley once, filled it with millions of gallons of rock, gravel, snow and ice.

3.Iceland has more than 200 geysers whose waters reach temperatures over 90o C. The name "geyser" comes from the Icelandic region called Geyser. Iceland is the first country in the world taking advantage of the geyser heat since 1910 for warming up dwellings. Today, Iceland uses geyser water for cultivating tropical crops in greenhouses (even bananas!), on the latitude of the Polar Circle.

The most famous geyser of Iceland is the Great Geyser, which, when resting, appears like a lake of 18 m (60 ft) in diameter and 3-4 m (10-14 ft) deep, and, when erupting, it gushes water jets 54 m (180 ft) tall for 10-15 minutes, at a temperature of 80-82o C. The jets take place at 25-30 hours distance. The canal mouth is 3 m (10 ft) wide. Its cone is made of silicon concretions. At 12 m (40 ft) deep into the canal, the water has a temperature of 121o C, but it does not boil because of the pressure of 2 atmospheres.

4.Other places on Earth where isolated geysers are found are Chile, New Zealand, California, Peru, Bolivia, Dominica, Azores, Kenya, Java and Japan.
The largest known geyser functioned in New Zealand between 1899-1904: "Naumangu" had a water column of 800 cubic meters of water and 457 m (1,523 ft) tall. New Zealand too uses the geysers' energy.

Prediksi Soal UAN Fisika 2008

Bagi Bapak/ibu guru yang butuh soal-soal Fisika untuk Try out, Modul Fisika hubungi kami dengan alamat pada blogspot di bawah ini. Kami akan segera mengirimkan via e-mail. Thank you God Bless You Forever...

Murid Bertanya

Ketika saya mengajar fisika tentang cahaya di kelas X SMA Stella Maris, seorang siswa saya bertanya:
John : Pak saya mau tanya ....
Guru : Silakan .....
John : Mengapa jika lilin yang nyala ditutup dengan kantong plastik lilinnya menjadi
mati....
Guru : Karena tidak ada lagi gas oksigennya sehingga lilinnya mati..
John : Bapak salah....
Guru : kaget sambil kesal (karena sudah puluhan tahun ngajar fisika disalah-salahin
oleh siswa kelas X) ???????
John : itu namanya kurang kerjaannnnn ha..ha..ha..
Guru : Buset....

Hanya Perlu Dua Potong Kulit Saja

Menurut Leonardo Da Vinci, kebanyakan manusia menganggurkan anugerah akal yang dimilikinya. Punya mata hanya untuk melihat tetapi tidak untuk memperhatikan, punya perasaan hanya untuk merasakan tetapi tidak untuk menyadari, atau punya telinga hanya untuk mendengar tetapi tidak untuk mendengarkan. Rugi amat ya?

Hanya Perlu Dua Potong Kulit Saja

Seorang Kaisar akan berkeliling negeri untuk melihat keadaan rakyatnya. Ia memutuskan untuk berjalan kaki saja. Baru beberapa meter berjalan di luar istana kakinya terluka karena terantuk batu. Ia berpikir .. , "Ternyata jalan-jalan di negeriku ini jelek sekali. Aku harus memperbaikinya."
Kaisar lalu memanggil seluruh menteri istana. Ia memerintahkan untuk melapisi seluruh jalan-jalan di negerinya dengan kulit sapi yang terbaik. Segera saja para menteri istana melakukan persiapan-persiapan. Mereka segera mengumpulkan sapi-sapi dari seluruh negeri. Di tengah-tengah kesibukan yang luar biasa itu, datanglah seorang bijak menghadap Kaisar. Ia berkata kepada Sang Kaisar, "Wahai Paduka, mengapa Paduka hendak membuat sekian banyak kulit sapi untuk melapisi jalan-jalan di negeri ini, padahal sesungguhnya yang Paduka perlukan hanyalah dua potong kulit sapi untuk melapisi telapak kaki Paduka saja." Konon sejak itulah dunia menemukan kulit pelapis telapak kaki yang kita sebut "Sandal".

Refleksi: Seringkali kita berharap dapat mengubah seluruh dunia beserta isinya, namun sesungguhnya yang diperlukan hanyalah mengubah diri kita sendiri. (adapted from The Song of Birds - Anthony de Mello).

Hari Yang Terindah

Pada hari ini saya pertama sekali membuat blogspot tentang belajar fisika. Fisika adalah suatu bidang studi yang sangat di takuti siswa baik siswa ditingkat SMP, SMA maupum mahasiswa di perguruan tinggi. Namun sudah banyak pakar fisika membuat belajar fisika menjadi mudah dengan usaha yang begitu tekun dan pengorbanan yang besar sehingga fisika sekarang sudah banyak diminati siswa. Belajar fisika adalah mengenal alam dan lingkungan kita. Dimana kita berada disitu ada ilmu fisika namun kita sering lupa atau cuek. Mari mulai hari ini kita sama-sama belajar fisika siapapun anda pasti anda tidak luput dari ilmu fisika......