Teaching Electricity

Electricity is a form of energy, a result of the existence of electrical charge. Its theory and inseparable effect is probably the most accurate and complete of all scientific theories. Because of it, invention of motors, generators, telephones, radio and television, medical gadgets, computers and nuclear-energy systems have taken place. However, the many terms and definitions of electricity make it quite hard to pick up by students. So here's an outline that can be used by anyone who might have a hard time lecturing about it.

1. What do a TV picture and lightning have in common? They are caused by tiny electrically charged particle called electrons. This flow or movement of electrons is what we call as electricity. Electrical charges cause television sets to work and telephones to ring.

2. What is static electricity? All matter is made of atoms and tiny particles held together by electric forces. Inside each atom are positively charged protons and negatively charged electrons. They are attracted to each other. A buildup of positive or negative charges is known as static electricity.

Example: When you brush your hair on a dry day, you may see sparks or hear a breaking sound. This happens because when you brush, many free electrons gather in your hair. Your brush does not have as many negative charges, so the charges from your hair get transferred to the brush.

3. What are conductors? They are what carry electric charges. Most conductors have many free electrons. A metal doorknob is an example of a conductor. Objects that generally do not conduct charges are called insulators.

During a thunderstorm in 1752, Benjamin Franklin flew a kite that had a metal tip connected to a silk string that acted as a conductor. A key was then attached to the string at a point near the ground. When Franklin touched the key it sparked and he could feel the electricity. Note that the next two who tried this extremely dangerous experiment were killed.

There is also a massive buildup of electrons in a cloud. You see lightning when the electrons are finally discharged or released to the ground.

4. Where does electrical energy come from? When you plug in an electric fan, you are not really using electricity. Instead you are using electric power. The source of this power is a generator. Large generators supply huge quantities of electric power to your community.
When teaching, your goals must be straight cut. Create an outline if you have to. It gives you a general flow of what you want to teach and allows you to check loopholes along the way. To prevent misunderstandings between you and your students, ask questions as well. As teachers, your role is to ensure you are effectively feeding the right information to your students.

Lebih Murah, Praktis, dan Bersih, dengan Biotoilet

Almere Poort HDR
Originally uploaded by Gerbren.nl

Biotoilet kini bisa dikembangkan secara sederhana untuk skala rumah tangga dengan menggunakan serbuk gergaji. Selain harganya lebih murah,juga bisa dimanfaatkan sebagai pupuk kompos.

Bagi masyarakat yang tinggal di wilayah padat penduduk dan sulit mendapatkan air bersih,tidak ada salahnya memanfaatkan teknologi biotoilet karya Lembaga Ilmu Pengetahuan Indonesia (LIPI).

Biotoilet merupakan toilet kering, tidak berbau, hanya membutuhkan ruangan 0,5 meter,dan harga membuatnya murah. Selain itu, sisa buangan kotoran bisa bermanfaat sebagai kompos untuk menyuburkan tanaman. Peneliti Fisika Lingkungan LIPI Sinta Neniwardani menyatakan, setelah sukses melakukan uji coba biotoilet di kompleks Pondok Pesantren Daarut Tauhid Bandung, kini proyek percontohan selanjutnya dilakukan di kompleks perumahan kumuh di Kiaracondong, Bandung.

Daerah wilayah Kiaracondong dipilih karena dengan luas yang relatif kecil sekitar 2 km persegi,tapi memiliki penduduk yang padat sekitar 30.000 jiwa. Karena itu,kompleks perumahan Kiaraconding cocok dijadikan laboratorium hidup untuk menguji biotoilet. ’’Kiaracondong merupakan wilayah padat, kering, dan sulit mendapatkan air bersih. Dengan segala keterbatasan yang ada,kami memilihnya sebagai pilot project yang semoga nantinya bisa ditiru daerah lain,” papar Neni ketika dihubungi SINDO.

Nini menjelaskan,butuh waktu sekitar tiga tahun untuk melakukan pendekatan kepada masyarakat dan memperkenalkan biotoilet tersebut. Sebab,masyarakat masih awam dan belum paham bahwa biotoilet bisa menjadi salah satu alternatif sanitasi yang ramah lingkungan sekaligus berwawasan ekologi.

Di beberapa titik Kiaracondong, banyak sekali terdapat WC umum yang suatu saat pasti bisa penuh dan tentu saja tak efektif untuk area perkampungan dengan lahan sempit. Selain itu, limbah biotoilet jelas bisa dimanfaatkan sebagai kompos yang bisa digunakan masyarakat setempat untuk menyuburkan tanahnya untuk bercocok tanam.

’’Masyarakat setempat benarbenar kami libatkan untuk membangun biotoilet ini. Awalnya,mereka tidak memberikan respons, tapi kini mereka mulai menyadari pentingnya toilet yang menghemat penggunaan air bersih ini,”paparnya.

Berdasarkan catatan Organisasi Toilet Dunia (World Toilet Organization/ WTO),rata-rata setiap orang pergi ke toilet 2.500 kali per tahun atau sekitar 6–8 kali per hari. Itu artinya, selama tiga tahun dari masa hidup manusia dihabiskan di toilet. Jika selalu menggunakan toilet konvensional, lama-lama tabung septic tank akan penuh.

Akhirnya, tidak ada lagi lokasi yang bisa digali yang bisa digunakan sebagai tabung septic tank. Untuk itulah dibutuhkan sebuah kreasi biotoilet yang tidak hanya berwawasan memanfaatkan lahan, juga mengubahnya menjadi investasi yang menghasilkan.

Menurut Nini, biotoilet merupakan desain toilet sistem kering yang mempergunakan matriks serbuk kayu sebagai media penangkap dan pengurai tinja dan urine. Tidak hanya itu, limbah dapur sisa makanan juga bisa diolah di sini untuk menjadi kompos. Ciri khas dari desain itu adalah tidak menggunakan air untuk menggelontor kotoran.

Sebab, itu langsung ditampung dalam tempat pengolah untuk ukuran tabung biotoilet 0,5 meter kubik dengan kapasitas 30–50 orang per hari.Setelah itu, serbuk kayu lama dapat diganti dengan serbuk baru dalam jangka waktu 3–4 bulan. Serbuk gergaji ini dapat dimanfaatkan sebagai media kompos tanaman.

Menurut Neni, biotoilet bisa digunakan sebagai WC yang ramah lingkungan yang cocok dibangun di daerah dengan kondisi sistem sanitasi yang belum memadai,kondisi lingkungan yang buruk, keterbatasan lahan, ketiadaan saluran buangan air kotor, dan kurangnya air bersih. Keuntungan secara teknis maupun teknis dari teknologi sederhana ini tidak menggunakan air.

Dengan demikian,menghemat pemakaian air bersih dan dapat langsung mengurai kotoran manusia. Berdasarkan penelitian LIPI, biotoilet ini mampu mengurai 60 persen feses manusia dalam 1 hari. Selain itu, toilet kering ini tidak menebarkan bau layaknya septic tank biasa, tidak memerlukan saluran pembuangan khusus, dan dapat digabungkan menjadi alat pengolah sampah dapur.

Bentuknya yang sederhana mudah dikonstruksikan dengan bahan yang mudah didapat. Tabung biotoilet dirancang dari bahan stainless steel yang tahan selama tiga tahun, yang tentu saja mencegah kebocoran dan tidak berkarat.

’’Jika dibuat secara massal, mungkin biaya yang dibutuhkan hanya sekitar Rp5 juta–Rp10 juta. Namun,hingga saat ini,kami masih mengembangkan konsep biotoilet sebagai WC umum, belum sebagai WC rumahkan. Akan sulit sekali mengajak partisipasi masyarakat yang berkecukupan untuk menggunakan toilet ini. Mereka lebih cenderung memilih toilet air, mempertimbangkan budaya, dan kepercayaan agama,”jelasnya.

Neni mengisahkan, awal ide dari pembuatan biotoilet berdasarkan pengamatan bahwa mayoritas penduduk Indonesia di wilayah pedesaan menggunakan cubluk sebagai toilet. Dengan hanya menggali sebuah lubang,kemudian bisa ditutup kembali dengan tanah ketika sudah penuh.

Sementara itu, biotoilet modifikasi LIPI ini merupakan toilet kering yang portabel bisa dipindah ke mana-mana. Desain WC kering rekayasa LIPI ini memiliki bentuk sederhana. Dari luar,WC kering LIPI ini mirip sebagai tempat kerja.Menurut dia,selain Indonesia, Jepang dan Skandinavia juga telah mengembangkan teknologi serupa.

Bagian penting biotoilet,antara lain lubang WC (duduk/jongkok), lubang aerasi udara, serbuk gergaji (bisa kayu atau bahan organik lain) yang digunakan sebanyak tiga perempat tabung penampungan, pemanas (bila diperlukan), pengaduk dengan menggunakan motor penggerak.

’’Sudah sejak dua bulan lalu,akhirnya masyarakat wilayah Kiaracondong mulai menggunakan biotoilet ini.Meskipun akhirnya secara perlahan, demi mendapatkan partisipasi masyarakat, kami pun menggunakan sedikit air dengan menggunakan shower sehingga air yang digunakan tidak terlalu banyak. Sebab, kalau terlalu basah, fungsi pengurai tidak akan berjalan dan tabung penampung akan cepat penuh,”paparnya.

Nini menambahkan, hambatan terbesar dalam penerapan biotoilet ini adalah soal budaya masyarakat. Bagaimana meminta masyarakat untuk membiarkan toilet ini tetap kering. Jika ingin cebok,bisa dilakukan di luar toilet. Namun, karena tuntutan budaya, kebanyakan masyarakat enggan melakukan hal itu. Kini, Departemen Pekerjaan Umum (PU) berencana menerapkan biotoilet di wilayah Nusa Tenggara Timur (NTT) yang sulit mendapatkan akses air bersih. (abdul malik)

Sumber : Seputar Indonesia (20 Oktober 2007)

Which Educational Technology Purpose(s) are served?

Which Educational Technology Purpose(s) are served?
Originally uploaded by Wesley Fryer

I'm thinking most technologies used for learning can be categorized into three functional categories or purposes: A funnel, a ruler, and an amplifier. Most K-12 schools seem to be using their technologies for the former two purposes, and ignoring or avoiding the latter.

The Art of Letting Go

By: mjb

Now here it comes, the hardest part of all
unchain my heart that's holding on
how do I start to live my life alone
guess I'm just learning, learning the art of letting go
-Mikaila

Many of us want a lot of things in life, material objects that can symbolize our status and success. Most people dream of owning a house and lot, having a successful career or business, and be part of a healthy and happy family. Aside from property and recognition, people also crave after the security and fulfillment of an intimate relationship. When we think that we have found a good partner, we are overjoyed and believe that life is now complete.

However, when things go wrong and the relationship reaches an end, we go through varied emotions that seem to rip our soul apart. We go through anger, despair, grief, sadness, and depression. We feel lost and adrift, unsure what our next move should be.

But there is an even more painful experience than ending a relationship. People who break-up or end up in divorce still have a chance, no matter how remote, of reconciliation or ending up as friends. But for people who physically lose their partners endure an even more painful separation. The death of a loved one brings about an incomparable level of pain. Losing people who are dear to us leaves us in grief and in confusion about how to go about the next important step: letting go.

Letting go of a relationship that has meant everything to us is not an easy thing to do. But whether we like it or not, it has to be done if we want to move on. No matter how hard we try, we cannot live in the past nor stay forever in the present. To live, we must move on and look to the future. To truly move on in life, we need to achieve closure from the past.
How do we let go and move on? Letting go of a relationship involves letting go of feelings and emotions such as anger, animosity and resentment that one may feel towards a partner. One should not bottle up emotions because it may even lead to some health problems. Allowing oneself to grieve over the loss of a relationship may be healthy, but there should be a limit to the amount of time we spend on grieving. While it is normal to be emotionally distressed by the loss of a loved one, it is not advisable to allow one's self to wallow in grief and sadness --- a negative emotional condition that can become a self-defeating habit.

One should also envision other possibilities and not to dwell on the “what-might-have-beens.” Letting go of a relationship involves recognizing that it was not meant to be and that one should set new goals and start to build a new life. A person in grief must eventually realize that the relationship has run its course and that it is time to let go.

Often, when we have been in a really good relationship for some time, we tend to lose of our identity. Letting go should also mean letting go of dependency. It is something that needs to be learned to enable a person to veer away from overdependency on others.

If one is to truly let go of a relationship, he or she has to forget all the apprehensions, worries, fear and anxiety of being alone. Ending a relationship doesn't mean that we have to close ourselves from falling in love again. It is true that relationships may entail experiencing some episodes of sadness, but they also come with moments of great pleasure. For many of us, life would not be complete without the combination of both.

Just as it takes two to tango, it also takes two to make a relationship work. One should not dwell on the past and think on what could have done better to make the relationship work. We all have been hurt and life always gives us some valuable lessons that will provide us some guidance for our journey ahead.

When one is ready to let go of a relationship and reconcile with the fact that the past is past, one can experience an enormous weight being lifted off the shoulders. There is a sense of accomplishment that will come out of the whole experience, making us a better person.

Article Source: http://www.e-zine.com

Choose Variety of High Quality Medicines at Online Medicines Enjoyed Reading this article? More here: Pharmacy Articles