Saturday, January 30, 2016

Penyusun tata surya

Bumi adalah planet yang satu-satunya diketahui memiliki aktivitas geologi dan memiliki makhluk hidup. Memiliki hidrosfer yang cair yang merupakan ciri khas di antara planet-planet kebumian. Bumi juga merupakan satu-satunya planet yang memiliki lempeng tektonik. Atmosfer bumi berbeda dengan planet lainnya, karena pengaruh keberadaan makhluk hidup yang mana menghasilkan 21% Oksigen. Bumi memiliki satu satelit yang bernama bulan.
·         Mars atau planet merah berrevolusi 687 hari dan berrotasi 24,6 jam. Planet mars memiliki dua satelit yaitu fobos dan deimos.
·         Yupiter merupakan planet terbesar yang mengelilingi matahari. Massanya 318 kali dari massa bumi. Kandungan utama yang membentuk yupiter adalah hidrogen dan helium. Yupiter mempunyai 63 satelit empat satelit terbesarnya yaitu Ganymede, Callisto, Lo, dan Europa. Ganymede satelit yupiter merupakan satelit terbesar di Tata Surya yang berukuran lebih besar dari pada planet Merkurius. 
·         Saturnus merupakan planet yang dikenal karena cincinnya. Saturnus memiliki massa 95 kali dari masaa bumi. Saturnus memiliki 60 satelit, dua diantaranya adalah Titan dan Enceladus yang mana telah menunjukkan aktvitas geologis, meskipun hampir terdiri dari es saja. Titan merupakan satu-satunya satelit yang memiliki atmosfer tersendiri. 
·         Uranus adalah planet paling ringan dengan massa 14 kali massa bumi yang dikategorikan. Inti uranus sangat dingin yang hanya memiliki pancaran sedikit energi panas. 
·         Neptunus merupakan planet yang sedikit lebih kecil dari Uranus, dan bermassa 17 kali dari massa bumi. Dia memiliki 2 buah satelit yaitu Triton dan Neroid. Revolusinya selama 164,8 tahun dan rotasinya 16,1 jam.





Learning of Natural Science in Primary Schools

Coverage materials Natural Sciences in Primary Schools

The scope of subjects Science includes two aspects: Scientific Work and Concept and Implementation. Scientific work include: investigation / research, scientific communication, the development of creativity and problem solving, attitude and scientific value; whereas Concept and Implementation. includes: Living things and life processes, namely humans, animals, plants and their interaction with the environment, and health; Objects / materials, properties and uses include: liquid, solid, and gas; Energy and changes include: the style, sound, heat, magnetism, electricity, light and simple aircraft; Earth and the universe include: the land, the earth, the solar system, and other celestial bodies; and Science, Environment, Technology, and Society (salingtemas) which is the application of scientific concepts and their interrelationships with the environment, technology and society through the creation of a simple technology works including designing and making.
All five are basic fields of physics, chemistry, and biology. Although the area is a Natural Sciences learning materials, learning not only involves the problem of knowledge. Learning of Natural Sciences notably more emphasis on the process of how students learn and the effects of the learning process for the development of the students themselves. Natural Sciences learning involves students 'activity, both physical activity and mental activity, and focus on the students, based on the students' everyday experiences and interests of students. Learning of Natural Science in elementary school has three main objectives: to develop scientific skills, understand the concept of Natural Sciences, and develop an attitude that is based on the values ??contained in the lesson.
How elementary school students studying Natural Sciences?
Learning is an active process (Rodriguez, 2001). Children learn how to construct things learned by the knowledge that he knew and not receive something passively. This understanding stems from konstruktivisma perspective. Konstruktivisma itself often found in various fields such as psychology, philosophy, sociology, and education, as well as significant implications in the learning of Natural Sciences.
This raises the question that how to make students active learning? And this question will determine how the teaching and learning of Science in elementary school, that learning of Natural Sciences is not only the determination and mastery of the material, but what aspects of Natural Sciences who need to be taught and in what way, so that students can understand the concepts being studied by good and skilled logically to apply these concepts to other situations that are relevant to their everyday experience.

Student interest in Natural Sciences is also important to study Natural Sciences effective, especially for developing confidence in the opinion, reasoned, and determine how to figure out the answer. In that case, a six-year students will have a meaningful learning experience that at this stage the students are able to develop the attitudes and values ??of learning of Natural Sciences. Students who are interested in Natural Sciences will feel that studying Natural Sciences was fun to be enthusiastic about how the lessons of Natural Sciences affected the daily experiences (Murphy and Beggs, 2003). How ignited interest and motivation in students who do not love the lessons of Natural Sciences?

b. Learning strategies Natural Sciences

Hands-on and minds-on approaches
Effective learning by doing "activities" (learning by doing). Nevertheless, the essence of "activity" in the learning of Natural Sciences is a "learning activity" (Fleer, 2007). In practice it is not uncommon that "activity" (hands-on science) itself is not accompanied by learning (Bodrova and Leong, 2007). In his article, Osborne (1997) asks provocatively: "Is doing science the best way to learn science?" Therefore, teachers need to provide opportunities for students to interpret the concept (minds-on approach) (Keogh and Naylor, 1996).
Placing students at the center of the learning process
Traditional teaching methods with expository approach should start to be reduced. Teachers are only downloading the transmission of knowledge is less stimulating students to learn actively. This does not mean that the method is not good lecture, or students do not undergo a process of learning. Variation of the learning process more triggers students to actively learn (Rodriguez, 2001). Placing students at the center of learning poses means providing opportunities for students to construct the learned based on the knowledge that he knew and interpret concepts, instead of providing information through text books (Dickinson, 1997).
Identification of prior knowledge and misconceptions students
It is not at all easy because of several factors led to elementary school students can not articulate very well what he knows. However, departing from what is useful to know the student to determine the effective learning plan (Harlen, 1996).
Constraints learning Natural Sciences
Konstruktivisma approach in teaching Natural Sciences are not easy to implement. Perceptions about the role of the teacher in the classroom, the school's role in children's education, perceptions and expectations of parents towards teachers and schools are still very contradictory with the perspective konstruktivisma and very difficult to change the paradigm that holds that the teacher is the only source of learning.
Limitations of teachers in the fields of scientific knowledge and feeling less confident to teach Natural Sciences is another obstacle. This is because most primary teachers are classroom teachers who teach multiple subjects (high workload). Teachers' perceptions of the Natural Sciences also determine the learning of Natural Sciences. Teachers who see the Natural Sciences as a collection of facts, concepts, or cause a theory of learning of Natural Sciences that are less meaningful. Although the teacher holds a strong commitment to educating students and believes that students need to study Natural Sciences, teachers become less enthusiastic and confident of their ability to study Natural Sciences. It is less stimulating students to learn actively (Dickinson, 1997). Commitment to improve the learning process of Natural Sciences is an important step in creating an effective learning process (Tobin, Briscoe, and Holman, 1990).
These problems, plus the national final examination system which places great emphasis on understanding the concept, is a dilemma. The system resulted in Natural Sciences is taught only as a collection of facts, concepts or theories (body of knowledge), especially in grades 5 and 6. The teacher felt the need to prepare students for the national final exams in a manner appropriate drilling so they can answer the question. The dedication of teachers to provide meaningful learning experiences for students in the field of Natural Sciences and provided supplies scientific values ??contained in the learning of Natural Sciences declined sharply along with preparation for exams.
In addition, the number of students in the classroom is the main obstacle of learning of Natural Sciences. The number of students in the top 20 children in one class cause difficulties to overcome the problem of teacher individual differences in ability. Another example is the availability of time constraints; a mismatch between the curriculum, teaching, and evaluation; limitations of learning resources; the pattern of relationships between teachers and students; and others.

c. The concept of Natural Resources

On the matter of Earth and the Universe, there is one component of the so-called natural resources. Natural resources are everything supplies or goods naturally in a state as found necessary human (Randall, 1987, in Notohadiningrat, 1992), or with a particular effort can be made useful to man (Menard, 1974, in Notohadiningrat, 1992). In its raw state, the resource can be input into the process of producing something of value, or it can be entered directly consumption process so as to have the price (Randall, 1987, in Notohadiningrat, 1992).

According to the constituent materials, natural resources terpilahkan be non-biological resources (water, soil, air, minerals, and energy) and biological resources (animals and plants). According to its behavior in normal use, there are renewable resources (water, soil, air, animals, and plants) and there are non-renewable (minerals and energy). But on the use limit has passed, can behave renewable and non-renewable resources within a human generation, since the rate of utilization beyond the rate of restoration of those resources themselves.

d. The concept of conventional energy

Energy and its amendment on the matter, there is a conventional energy or fossil fuels. In the English dictionary, the fuel is defined as a substance that is burned to produce heat or power. Heat obtained from the combustion process, wherein the carbon and hydrogen in the fuel reacts with oxygen and release heat. Procurement of energy as heat or power, either in the form of mechanical or electrical, is the main reason fuel combustion. The term energy, when used accurately in energy statistics, refers only to heat and power, but freely used by many people to include fuel as well.
Energy has always played an important role in the development of human life and economic growth and social welfare. For example, fuel wood has been used since ancient times to make fire, and the first human civilizations have used wind to sail abroad.
Firewood when it was discovered abundant and free. People are still living in remote places. When the villages and small towns have sprung up, then firewood turned into a commodity trade. With the ever-expanding city, demand for energy has increased significantly, so the forests began to be exploited excessively resulting in a scarcity of firewood in various regions. In connection with this, the nascent awareness for supervising the supply and demand for fuel wood.
Without the heat from the burning of fuels, human activities will be limited and hampered. Modern society is more and more use of energy in industry, services, housing, and transportation. The most obvious example is oil, which is the most commercial commodity. However, keep in mind that both oil and other fossil fuels, such as coal and natural gas, a non-renewable natural resources. The combined effect of rising demand and depletion of natural resources makes us need to monitor the energy situation. Other factors that require deeper knowledge about energy supply and demand is the problem of dependence, endurance, and energy savings as well as environmental problems. Use of hydrocarbon fuels causes environmental damage due to high carbon dioxide emissions, which contribute greatly to global warming.

e. Alternative energy concepts

Alternative energy is a term that refers to all the usable energy that aims to replace conventional fuel without unintended consequence of it. Due successfully lowered production costs, renewable energy such as biofuels, solar, wind, etc., will continue to grow rapidly to 15 years, and would be excellent both investors and consumers, and can be the best replacement for energy sources Conventional biofuel or fossil / non-renewable. But the development of renewable energy is still quite long still need technology to overcome a number of problems.

The challenge of renewable energy

Because the issue of environmental sustainability, renewable energy continues to receive special attention and support from the governments of several countries (like the US and Canada), but for long-term customers and investors are more likely to be away from him for suggesting that renewable energy technology is not yet mature, with high production costs, the price is expensive, and thin profits.
Along with the increasingly high technological capabilities and declining production costs, renewable energy industry is now beginning to transition. Within the next 15 years the conventional energy industry will face a tough challenge, "corporations, governments, and investors will reconsider their investment plans carefully to avoid losses."
Conventional energy industry (such as coal, petroleum, and natural gas) will continue to be a huge market with a sizable profit, and will not be as easy as it vanished. In addition, the technology in the conventional energy industry (such as the engineering of power plants with coal) as well as the transition or transformation of plant equipment in this industry are basically too costly.
"Despite the challenges, before 2020, the conventional energy (such as coal, petroleum, and natural gas) will continue to be the main energy source for the whole world."

Biofuels high level

Production costs to produce biofuels from fibers that have been disposed of and the decayed, straw, weeds, leaves, or animal feed, would be equivalent to the cost of gasoline production before 2015, or down to 10 US cents per KWH, and will be a serious rival for conventional fossil energy sources. The current technical barriers to produce bio fuel high levels (such as ethanol produced from raw materials of non-food) are: build the infrastructure of transportation and equipment storage, as well as producing cars which utilize bio fuels high-level or mixed fuel (such as gasoline blended with ingredients a high level of bio fuels).

Solar power is a liquid

Now technology that utilizes solar energy to heat water that is then used to generate electricity has become more mature, and the cost has been reduced to be the same with the cost of conventional power generation technologies (such as brick coal to generate electricity).
However, although solar energy can be stored in the form of hot liquid, but it is difficult to be distributed - this is what has now become an obstacle in the dissemination of solar energy utilization tangible this fluid.

Photovoltaic solar energy

By using photovoltaic panels, sunlight can be directly transformed into electrical energy. The development of photovoltaic technology has now also been developed such that the production cost can be reduced. Until 2020 the cost of photovoltaic solar energy production will be equal to the cost of production of other energy sources, and will have high competitiveness. The total capacity of worldwide electricity that can be generated with photovoltaic technology will reach 120 ~ 140 billion watts by 2015, or about 6 ~ 7 times the capacity of electricity production in 2009 only amounted to 20 billion watts.

Wind power

Wind power can be divided into two types namely onshore wind power (onshore wind) and marine wind power (offshore wind). When compared with other renewable energy sources, wind energy technology is already highly qualified. In some places, the cost of production of power units with onshore wind power is the same as conventional power generation technology, and even continued to show a downward trend. It is estimated that in 2015, the cost of power production by wind power can be reduced again by 15%, reaching 12 ~ 13 US cents per KWH.
According to statistics from the Canadian Wind Energy Energy Association (CanWEA), in the last decade, the growth rate of wind power worldwide has reached 25%. And in 2020, the total value of investment in the energy sector of wind power worldwide will reach 1 trillion US dollars, with an annual power capacity of more than 6 trillion watts per year. But wind power constraints are: the need for vast land, which is usually difficult to obtain permission from the government, and it is difficult to store the electricity generated.

f. The integration of Islamic values ??in science teaching

Urgency integration of the values ??of Islam which contains at IPA spiritual values ??are: First, integration is done as worship and command execution Allah. Secondly, integration is done to give worship at all aktivias science and life associated with the process and results of science. Third, the integration is done with the aim of eliminating the dichotomy between public science and theology as well as strengthen mutual support between scientific knowledge with the values ??of Islam. Fourth, integration conceived with the aim to assert that the science is not neutral either in the process, as well as the application of science, but the intervention of religious values. Fifth, the integration is done as a way to enhance human beings in worship to Allah. Sixth, the integration is done with the aim to enable people to understand that both science and religion come from the same source, namely God Almighty. Seventh, the integration of the value of religion, science, and other related aspects need to be internalized through a model that can be tested in the future.