HannahM

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=Reflections =  The height of firing a projectile affects the time it takes for it to hit the ground in that a higher height will take longer. The height affects the distance the projectile travels in that a greater height will cause the projectile to travel further. This is because the object travels at the same speed when it is released but if it is fired at a greater height, it can travel further horizontally before hitting the ground. The equation to find velocity is velocity = distance / time, so if it were rearranged to determine distance, the equation would be distance = velocity x time. In comparing two distances of projectiles, where one is fired from a greater height, the velocities would still be the same. Since it has already been determined that a greater height would take longer for the projectile to reach the ground the time would be more for the higher object. The object that takes longer to hit the ground would travel further which is shown by the equation. How does the horizontal speed of a projectile affect the time to hit the ground? How does it affect the distance the projectile travels? The horizontal speed of a projectile doesn't affect the time for it to hit the ground because the equation for velocity is distance divided by time. If you were calculating for time the equation would be distance divided by velocity. If the velocity were increased and the distance it traveled increased, then it would still be proportional and the time it took to hit the ground wouldn't change. It could travel further but since it is traveling at a faster velocity, it takes the same amount of time to travel that further distance. How does the vertical speed of a projectile affect the time to hit the ground? How does it affect the distance the projectile travels? The vertical speed affects the time to hit the ground and is related to the angle at which the projectile is fired. If the projectile is fired at a greater angle less than or equal to 45 degrees to the ground, the projectile has a vertical velocity and moves upward, reaches a max height, and then drops again. If the object was fired from an angle greater than 45 degrees, the object would have a greater vertical velocity. The greater the vertical velocity, the longer amount of time it takes for the object to hit the ground, but the less distance it travels. If the vertical velocity is greater and it travels upward and then drops it will not travel far because it uses more energy to travel vertically instead of horizontally. || These two laws of thermodynamics apply to the labs we have done in class: collisions of carts, mechanical equivalent of heat, energy on a ramp, roller coaster, and calorimetry. It applies to the Collisions Lab in that energy was converted from potential energy when it wasn't moving to kinetic energy when it collided with another cart and set it in motion. Some energy was "lost" (in that it couldn't be recovered to be used to perform work) during the collision. For example, some energy was converted to sound energy or heat energy when the carts collided with one another. The two laws apply to the Mechanical Equivalent of Heat Lab in that the energy was converted from kinetic energy to heat energy. Kinetic energy is more useful because it's the energy of motion and has more prominent uses. The thermodynamic laws apply to the Energy on a Ramp Lab because energy was converted from gravitational potential energy (due to the incline of the ramp) to kinetic energy when it was released and rolled down the ramp. Some energy was converted to less useful forms in that gravitational potential energy and rotational energy were both converted to kinetic energy. The Roller Coaster Lab was affected by the two laws in that energy was converted from gravitational potential energy to kinetic energy. Energy was changed into a less useful form which could be seen as the cart moved down the track losing momentum as it's gravitational potential energy decreased. The first two laws of thermodynamics applied to the Calorimetry Lab in that heat energy was transfered from one object to another and it was converted to a less useful form in that it was divided into objects and therefore had lower separate energies. || Temperature is directly proportional to the average kinetic energy along a straight or curving path, but not to be confused with total kinetic energy. These three, kinetic energy, temperature, and heat, are related in that the temperature, or average kinetic energy, of an object or substance determines whether or not heat will be transfered and how. The higher the temperature the higher the amount of kinetic energy. ||
 * == Agents of Climate Reflection; January 7, 2010 == ||
 * In the "Agents of Climate" reading, the author explains that all of the short-term weather variations as well as the patterns over long periods of time are driven by the electromagnetic radiation from the sun. The temperature of the mass that is radiating affects the number of photons it emits. The sun is extremely hot with a surface temperature over 5000 degrees Celsius so it emits many photons mostly at a wavelength of about 500 nanometers, which is yellow-orange in the visible spectrum. Other radiation emitted by the sun is ultraviolet and infrared, and this energy moves 300,000 km per second. Climate is an effect of the solar radiation interacting with and transferring to the gases in the atmosphere as well as the Earth's surface. Levels of the atmosphere absorb different sized wavelengths depending on the major absorbers (N2, O2, N, O, etc) in that section thereby creating an organized structure to the atmosphere. These absorbing molecules are known as greenhouse gases. Approximately half of the radiation that starts the journey through the atmosphere actually makes it through to heat the soil, water, and vegetation of the Earth. In addition, the Earth emits radiation to the atmosphere but some of it is absorbed by the atmosphere creating kinetic energy among the molecules therefore warming the atmosphere, itself. In terms of earth's energy budget, it's radiation budget is in balance because the outgoing radiation is equal to its incoming radiation. An analogy used by scientists in order to explain measuring income vs expense to determine if the budget is in balance is a tub of water with multiple faucets and drains of varying sizes. Different techniques can be used in order to calculate the amount or rate supplied by the faucets as well as the amount or rate removed by the drains. The process of finding the amount in the tank/reservoir to determine and measure the supply, removal, and balance is called an Earth system budget analysis. This tank or reservoir represents something such as the atmosphere as a whole or sections of it. The faucets and sinks are rates of creation and destruction; representative of solar energy, evaporation of water, conversion of methane to carbon monoxide, transfer of ozone between parts of the atmosphere,etc. ||
 * == Scientific Imagination Reflection; December 15, 200 9 == ||
 * The authors of the article "Scientific Imagination" talks about dealing with the difficulties of describing and understanding something that is invisible. They try to explain the electromagnetic field and the points and waves in it. He also explains that what you visualize as the truth still has to be consistent with and agree with the known laws of physics. In addition to this, he speaks of the beauty of things that are unable to be seen with the naked eye, such as the reflection coefficient of a sodium chloride crystal. Equations that show laws and results are also sometimes considered beautiful but there has to be some basic understanding of the topic being discussed to understand the authors' point of view on the topic of visualization, intellectual beauty, and scientific imagination. ||
 * == Projectile Motion Reflection; November 1, 2009 == ||
 * How does the height of firing of a projectile affect the time to hit the ground? How does it affect the distance the projectile travels?
 * == Calorimetry Lab Reflection; October 14, 2009 == ||
 * To measure the heat of fusion by heating paraffin until it melted would be done by placing the tube of solid paraffin into a calorimeter of hotter water so that the heat from the water would transfer to the paraffin (which has a lower temperature). The advantages of this technique include: ability to measure the temperature of the solid paraffin, and temperature of liquid paraffin (instead of just the 100 degree C water that it was in for the lab we did). The disadvantages of this technique include: the heat from the water would transfer into the calorimeter and tube so those would have to be accounted for, and the water temperature would have to be really high because if the solid paraffin temperature was low and the two evened out, the paraffin might still not become a liquid. ||
 * == Energy Rules in Previous Labs Reflection; October 11, 2009 == ||
 * There are two basic rules of energy: "energy is conserved, and energy always goes from more useful to less useful forms." Energy can be changed from one form to another but the total amount stays the same because energy cannot be created or destroyed: the first law of thermodynamics. When energy is converted, it's always from a more concentrated or more useful form to a less concentrated or less useful form. This limits the amount of energy that can be used for work and is known as the second law of thermodynamics.
 * == Temperature, Heat, and Kinetic Energy Reflection; October 3, 2009 == ||
 * Kinetic energy is the energy of motion. Heat is the energy that moves from an object or substance of higher temperature to that of a lower temperature. Temperature is the measure of how hot or cold something is on a standard scale: Celsius, Fahrenheit, or Kelvin.
 * == Energy Reflection; September 27, 2009 == ||
 * Work is the amount of force applied to an object over a certain distance. The two important parts of the concept of work is the application of a force and the movement of something due to that force. There are two groups of work: that which is done against another force; and that which is done to change the speed of an object. Kinetic energy is energy related to the movement of something. It depends on the mass and speed of an object. Potential energy is energy that is stored and ready to be used; it is in this state because of its position (i.e. a stretched rubber band or a compressed spring). These three, work, kinetic energy, and potential energy, are all measured in joules The law of conservation of energy states that "energy cannot be created or destroyed. It can be transformed from one form into another, but the total amount of energy never changes."

These four are related in that they all play a role on each other and can affect the result of another. Gravitational potential energy is related to work in that work is needed to move objects upward against gravity therefore giving it potential energy. Kinetic energy of a moving object is related to work in that it is equal to the amount of work that is needed in order to get the object to that speed from a state of rest. The law of conservation of energy consists of different forms of energy such as kinetic and potential energies in which force plays a role. A specific example of how the four are related and act together is shooting a boulder from a catapult. Work is done to pull back the catapult, the compressed spring that powers it now has potential energy, and when it is released, it has kinetic energy. The law of conservation of energy plays a role in this event in that the potential energy is equal to the kinetic energy. It is also possible that some energy was converted to a different type when the boulder hit its target; heat energy could have been produced. Despite whatever energy changed, the amount would still all be equal. ||
 * == Systems Reflection; September 20, 2009 == ||
 * According to physicists, a system is "any object, or set of objects that we wish to consider" that can and might interact with each other. My definition was a group of objects that can work together and interact in a process for some kind of purpose. These definitions are pretty much the same except for the fact that I thought that the objects interacting were doing so in order to produce something or go through a process.

The concept of a "closed" or "isolated" system is important when considering the conservation or mass and/or the conservation of momentum. The Laws of conservation of mass and momentum are only applicable in a closed or isolated system which are in some way closed or isolated from the rest of the environment or universe. When mass conservation is being observed, a closed system has to be used so that mass cannot be created or destroyed by some other source. When the conservation of momentum is being studied, an isolated system is necessary so that no net force from outside sources is influencing the studies. || The process we used in order to design and test a clock was similar to the scientific method in that we used most, if not all, of the parts of the method. We had preconceptions, predictions, observations, experiments, data, and patterns to identify. Our preconceptions are what caused us to choose to work with a mass/spring system or pendulum system based on which we just thought would work better. Our predictions were things like whether adding weight would slow down or speed up the frequency. We conducted experiments in order to figure out which weight would be best and once we had found that we collected observations and data. Studying this data allowed us to determine patterns to come to a conclusion.
 * == Simple Harmonic Motion/Clock Lab Reflection; September 14, 2009 == ||
 * // 1) How was the process of designing and testing a clock similar to the scientific method as discussed in class?

2) How did it differ? The process we used in order to design and test a clock was different from the scientific method in that we didn't have specific steps or process to follow or consider. We just experimented to come to a conclusion and then looking back, we did end up following parts of the method, but not in a step-by-step way.

3) What "steps" in the scientific process were present and which were missing? The steps that were present were preconceptions, observations, experiments, measurements, identifying patterns, and predictions. Steps that were basically missing--although were present in some aspect-- was hypothesis, theory, and/or law.

4) Was there a part of the activity that is not a part of the scientific process? To start the problem solving, we just tested different weights, using a guess-and-check system. This is essentially the experimenting stage of the scientific method but in a more random, unplanned way.

Julia and Hannahs Clock Experiment // || I have an explanation that goes with it though... The hypothesis, law, and theory can all result in a prediction. These three are tested by making predictions based on their statements. Predictions are educated guesses on what will occur in an experiment, which it leads to next. The experiment has results that are observed: next step of observations. Observations can lead to theories, laws, and facts. In addition, observations give experimental data, which can result in patterns. These patterns can be observed causing more questions in which a new hypothesis is made. Many connections can be made between these stages in the Scientific Method. They are all related or connected somehow, even if it is through a few steps. || (7) Hypotheses, theories, and predictions are what fuel the scientific method because they provide the question or statement that is being tested or observed. They provide a reason to continue with and pursue deeper understanding of how the world works by breaking it down into smaller, more manageable areas to be questioned, tested, and worked with. (8) Observations and experiments are not the same in the context of the scientific method. The actual words tell the difference between the two. Observations are things you notice or see when you watch and study something of focus. The person making the observations do not interrupt with the normal behavior of what it is they are studying. Experiments are different in that the scientist manipulates the conditions, testing how certain changes cause a difference in behavior. (9) The term //scientific cycle// would be a good substitute for //scientific method// because the parts of the method are not steps in that they need to be followed in order. It doesn't matter where the "cycle" is entered from or where it starts because eventually they will continue around the circle, completing all the parts. || Observations and compared to experiments in that observations are done without manipulating nature and experiments are where nature is manipulated and then the results of the manipulation are observed. These observations and experiments need to be done and recorded in such a way that they can be compared and reproduced by other scientists. The hypothesis, a "tentative educated guess", is one of the four titles into which scientific discoveries can be broken into. These groups are facts, hypotheses, laws, and theories. Facts are basic, commonly known observations. Laws are found when lots of observations and measurements all lead to a predictable pattern of nature. A theory is a confirmed, "explanatory description" that is proven by experiments and tests. It "represents the highest level of scientific discovery and achievement." Predictions are used in order to test scientific discoveries: hypotheses, laws, and theories. The prediction is made, the conditions are tested, and the results are observed in order to see if the experiment behaved as expected. THe tests that are done aren't always to prove something wrong or right, but to narrow down the conditions, in which the hypothesis, law, or theory is, indeed, correct. But these confirmations do not necessarily finalize the exact law or theory because **"every law and theory of nature is subject to change, based on new observations." ** ||
 * == Scientific Method Concept Map; September 9, 2009 == ||
 * I have a concept map, but I couldn't transfer it on here so I'll print it out.
 * == Scientific Method Review Questions 6-9; September 1, 2009 == ||
 * (6) The steps of the scientific method are initiated by preconceptions and then lead to the hypothesis, prediction, observations/experiments/data, and identifying patterns--but not necessarily in this order. Preconceptions are ideas or beliefs that spark a question that causes an entrance into the cycle. The hypothesis is an educated guess on which to base the scientific method process. Laws or theories can take the place of the hypothesis. Predictions are made in order to test the hypothesis, law, or theory. Predictions are educated guesses on how nature will react to certain conditions. These predictions are then tested. Observations, which are of un-manipulated conditions, and experiments, which are observations of manipulated conditions, are the next "step" of the scientific method. Data is collected from the observations or experiments. The last part of the scientific method is to identify patterns. This is pretty self explanatory-- patterns are found in order to determine conditions for the situation, prove, disprove, or change the hypothesis, law, or theory.
 * == Reflection on Scientific Method; August 30, 2009 == ||
 * The scientific method from the author's point of view is not a very specific, step-by-step list of instructions, but instead more general guidelines to go by when conducting an experiment or learning about the physical universe. These steps--observation, hypothesis, prediction, and testing--are elements of the scientific method that are just that: elements. They don't need to be followed in an exact order; instead, the scientist is able to start anywhere and will eventually complete the cycle throughout the four stages.
 * == Reflection on Online Tools; August 28, 2009 == ||
 * I like using online tools such as wikispaces because they are a quick and easy way to gain information and communicate with others. I have easily accesible internet access outside of school. I think that a valuable aspect of wikispaces will be the help it will provide in completing tasks such as homework and projects, and it is a good way to communicate with classmates that I might not be able to get ahold of otherwise. ||

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