JuliaK

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Agents of Climate; January 10th, 2010
The article Agents of Climate discusses climate and how it applies to the greenhouse effect and the energy balance. The stimulus that drives climate is the electromagnetic radiation energy from the sun. Electromagnetic radiation is conceptualized as a stream of photons. Heated masses of material, such as the Sun or planets, gives off photons. Ozone is one of the main absorbers of these photons. Each absorption of a photon by ozone results in a small amount of heat to the portion of the atmosphere near where the absorption occured. This absorption provides the energy to heat the stratosphere and much of the mesosphere. Thus a decrease in ozone leades to an increase in the intensity of the most energetic radiation reaching Earth's surface. The portion of solar radiation that is not absorbed during its passage through the atmosphere heats the Earth on which it falls. The outgoing solar radiation is also absorbed by atmospheric molecules. The absorption of these photons increases the internal vibrational and rotational energy of the absorbing molecules. This excess energy is then transfered to the atmosphere as kinetic energy or heat and so the Earth, warmed by the Sun, warms the atmosphere. Of the total incoming solar radiation, an average of slightly less than 30% is returned to space. Another 25% is absorbed within the atmosphere. The remaining 47% warms the Earth's surface. Of the solar energy absorbed at the surface, a little more than half is transformed into latent heat which is then released again into the atmopshere when water vapor condenses into clouds. Other significant amounts of surface heat energy are transferred back into the atmosphere by convection and turbulence and the absorption of Earths infrared radiation by greenhouse gases. Only a net 18% of solar energy is lost to space by radiation. Carbon dioxide, clouds, and water vapor efficiently retain the remainder. Of the 114 units of energy that are emitted, some 96 units are retured to heat the planet. This highly efficient cycling of energy produces the greenhouse effect. Careful study of the Earth system will show that the radiation budget is in balance. The planet achieves this balance by adjusting its own temperature.

Scientific Imagination; December 15th, 2009
The article Scientific Imagination by Richard P. Feynman, Robert B. Leighton, and Matthew Sands discusses the difficulty of imagining scientific concepts or ideas such as electromagnetic fields. This is because we have no picture of what an accurate electromagnetic field would look like and have no means of making one even remotely like what the true waves would look like. Taking it from a mathematical view it is still very difficult; imagining numbers at every point is nearly impossible. Even if taken from a mathematical perspective we are still limited to abstractions, using instruments to detect the field, and mathematical symbols to describe the field, etc. It is even more difficult to imagine these things within the constraints of everything else known in science. Imaginations are limited to laws of nature and the conditions which come from knowledge of the way nature behaves. Beyond that it is difficult to imagine the beauty coming from a diagram or a plot. How do we know what is beautiful like we know a rainbow is beautiful? This is nearly impossible to know or see this, but intellectual beauty can be found.

Reflection on the Firing of a Projectile; November 1st, 2009
The height of the firing of a projectile affects the time to hit the ground because, depending on how high the projectile is fired, the more time it will take for the projectile to hit the ground. When a projectile is fired into the air at a great height, a larger distance is travelled by the projectile. This is opposed to the smaller distance a projectile travels when being fired a shorter height into the air. The horizontal speed of a projectile affects the time to hit the ground in that, the farther a projectile travels horizontally, the greater amount of time it is in the air, thus it will take more time to hit the ground than a projectile with a small horizontal velocity. The horizontal speed also affects the distance the projectile travels in that the greater the horizontal speed, the greater the amount of time it is in the air, thus the greater distance the projectile travels. If it did not have a great horizontal speed, the object would not stay in the air as long, thus not travelling as great a distance. The vertical speed of a projectile affects the time before it hits the ground, in that the greater the vertical speed the longer it will remain in the air, thus the longer it will take to hit the ground. It will also travel a greater distance upwards if it has a greater vertical speed, because the speed means that the projectile will attain a greater height, or distance upwards.

== Reflection on the Simple Harmonic Motion Lab; September 14th, 2009== The process of designing and testing a clock was similar to the scientific method as discussed in class in that, like the steps of the scientific experiment, we had preconceptions about the outcome of the question which led to hypotheses, predictions, experiments/observations/data and identifying patterns. It differed in that we were mainly trying to accomplish something our "employer" gave us to do, instead of answer a specific question. The "steps" in the scientific process that were present were preconceptions, hypotheses, predictions, experiments, observations, data, facts, and patterns. Laws and theories were missing, because although we observed patterns multiple times, we had no constant observations that would lead to scientific theories or laws. Yes, there was a part of the activity that was not part of the scientific proccess because instead of choosing our own questions and experiments, we were "employed" to experiment and solve a problem. Julia and Hannahs Clock Experiment

Reflection on The Scientific Method; August 30th, 2009
====In earlier years, observations were thought to be useless in understanding the universe. It is now believed that observations, or the observing of nature without munipulating it, are essential to understanding it. Hypotheses are one of four groups that compose scientific discoveries. Facts, laws, and theories are the other three groups. Facts are simply confirmed observations about the natural world, hypotheses are a tentative educated guess, laws are regular predictable patterns of behavior in nature, and theories are well-substantiated explanatory descriptions of the world based on a large number of independently verified observational and experimental tests. Predictions are beliefs on how a particular system will behavior. Testing a prediction serves to define the range of situations under which the idea is valid.==== ====Patterns and regularities can be found within observations. When this happens, the results can be summarized in mathmatical form. These measurements can be very useful in creating the most accurate description possible. Thus mathmatical formulas are often used in the scientific method.==== =Reflection on First Use; August 28th, 2009=

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