Senin, 31 Maret 2008

Penelitian Tindakan Kelas (PTK) Bagi Guru

Penelitian Tindakan Kelas (PTK) memiliki potensi yang sangat besar untuk meningkatkan pembelajaran apabila diimplementasikan dengan baik dan benar. Diimplementasikan dengan baik di sini berarti guru mencoba dengan sadar mengembangkan kemampuan dalam mendeteksi dan memecahkan masalah-masalah pendidikan dan pembelajaran melalui tindakan bermakna yang diperhitungkan dapat memecahkan masalah atau memperbaiki situasi dan kemudian secara cermat mengamati pelaksanaannya untuk mengukur tingkat keberhasilannya. Diimplementasikan dengan benar berarti sesuai dengan kaidah-kaidah penelitian tindakan.

Langkah-langkah Penelitian Tindakan Kelas

Selasa, 25 Maret 2008

Applications of Newton's First Law

      * Consider some of your experiences in an automobile. Have you ever observed the behavior of coffee in a coffee cup filled to the rim while starting a car from rest or while bringing a car to rest from a state of motion? Coffee tends to "keep on doing what it is doing." When you accelerate a car from rest, the road provides an unbalanced force on the spinning wheels to push the car forward; yet the coffee (which was at rest) wants to stay at rest. While the car accelerates forward, the coffee remains in the same position; subsequently, the car accelerates out from under the coffee and the coffee spills in your lap. On the other hand, when braking from a state of motion the coffee continues forward with the same speed and in the same direction, ultimately hitting the windshield or the dash. Coffee in motion tends to stay in motion.
    * Have you ever experienced inertia (resisting changes in your state of motion) in an automobile while it is braking to a stop? The force of the road on the locked wheels provides the unbalanced force to change the car's state of motion, yet there is no unbalanced force to change your own state of motion. Thus, you continue in motion, sliding along the seat in forward motion. A person in motion tends to stay in motion with the same speed and in the same direction ... unless acted upon by the unbalanced force of a seat belt. Yes! Seat belts are used to provide safety for passengers whose motion is governed by Newton's laws. The seat belt provides the unbalanced force which brings you from a state of motion to a state of rest. Perhaps you could speculate what would occur when no seat belt is used