Teori Tata Surya

Teori-teori tata surya antara lain sebagai berikut.
1. Teori Planetisimal
Berdasarkan teori planetesimal tata surya terbentuk dari sebuah bintang yang lewat cukup dekat dengan matahari, di saat awal pembentukan matahari. Kedekatan tersebut membuat tonjolan pada permukaan Matahari, dan bersama proses internal Matahari, menarik materi berulang kali dari Matahari.
Pengaruh dari gravitasi bintang membentuk dua lengan spiral matahari yang berbentuk memanjang. Sebagian materi tertarik kembali dan sebagian lain akan tetap berada di orbit. Bagian yang berada di orbit akan mendingin dan memadat, dan menjadi planetisimal yaitu benda-benda dengan ukuran kecil dan yang berukuran besar disebut dengan protoplanet. Objek-objek tersebut kemudian saling bertabrakan dari waktu ke waktu sehingga membentuk planet dan bulan, sedangkan sisa-sisa materi lainnya menjadi komet dan asteroid.
2. Teori Pasang Surut Bintang
Menurut teori pembentukan tata surya ini bahwa planet terbentuk karena mendekatnya bintang lain ke arah Matahari. Kedunya saling bertabrakan menyebabkan tertariknya sebagian besar materi dari matahari dan bintang lain tersebut oleh gaya pasang surut yang dimiliki oleh kedua benda tersebut. Kemudian terkondensasi menjadi planet. Teori ini dikemukakan oleh James Jeans pada tahun 1917. Akan tetapi dipatahkan oleh seorang astronom bernama Harold Jeffreys tahun 1929 yang menyatakan bahwa tabrakan mengenai hal itu tidak mungkin terjadi, yang kemudian diperkuat oleh pernyataan Henry Norris Russell.
3. Teori Bintang Kembar
Berdasarkan teori bintang kembar bahwasanya dahulu kala tata surya ini terdiri dari dua bintang yang memiliki ukuran yang hampir sama dan letaknya berdekatan dimana salah satunya meledak meninggalkan serpihan-serpihan kecil. Adanya gravitasi dari bintang yang tidak meledak tersebut membuat serpihan-serpihan tersebut mengelilinginya. Terori ini dicetuskan oleh  Fred Hoyle (1915-2001) pada tahun 1959.

teori pembentukan tata surya nebula

anggota tata surya beserta gambarnya

gangguan sistem pencernaan pada manusia dan cara mengatasinya

perpindahan kalor secara radiasi terjadi pada peristiwa

contoh soal suhu dan kalor serta pembahasan

pengertian kalor kapasitas kalor dan kalor jenis

pengertian kalor laten dan kalor lebur

pengertian revolusi bumi dan pengaruh revolusi bumi

The Story Lessons Elementary School

The eldest several times asked me about her homework in PE lessons LKS book Grade 4 who could not answer. To find the answer, I usually point back to the first introduction to the theory that re-read to completion. In addition to theory, it is usually also accompanied by examples of questions, so that exercises can be done based on the theory and the examples that have been discussed. If it is still difficult to understand the theory and examples, new may ask.

This time is different. There was no theory in the introduction to the referenced matter. There was no explanation of how to search for answers. If during the first elementary school, I'll look to the library, mass media, or ask the person to better understand, usually in older people. Now, for those who are accustomed to playing Internet, may immediately be answered "There's always Google" or "Ask Facebook, Twitter or WhatsApp". Now, times have changed.

Problem

To seek answers that question is no effort to do the student, no answer came instantly play like magic. Even to become a magician must exist first effort is not easy. Positively, I believe this effort is the core process of learning, that to get the right answer is not obtained easily. Perhaps teachers have been taught in the classroom, so that students must first seek to work hard and perform other creative efforts hinggga find the correct answer. If you are still having trouble, then the student should do other business, either by asking parents, siblings, discussions with friends, looking for references on the Internet or the library literature.

The problem is, a lot of children of primary school age were not enough to understand themselves understand what the teacher is, sometimes even teachers are not taught before and have no clue how to find the answer in the book other than the LKS. Often, the teacher said, "Do homework so until umpteen pages, collected tomorrow!" That's it, no explanation at all. If that were the case, there is almost no difference between the way teachers teach primary school children (pedagogy) by way professors teach students (andragogi).

Solutions

Probably many ways to overcome it, and one solution in my opinion is to not get bored teachers remind students to do homework, while giving "clue" or the instructions to do it. If it involves the use of the Internet, should it be delivered to students by considering students are able to use the Internet in accordance levels. Of course, this condition requires that schools already teach the students about the use of the Internet for teaching and learning activities. If you have not been taught, use the Internet at least need assistance.