equation.pngequation_111.png ----
​​Monday, December 7, 2009

Today in Physics, we first looked over our Momentum tests that we had taken on Friday. Mr. Rylander reviewed the short answer portion and then we could ask any questions that we still had. The test was out of 52 points. Then, Mr. Rylander talked about our new unit. The test is going to be on Friday, December 18, and that is also the due date of this unit's WebAssign. There was no question of the day today. We were also given a worksheet to finish for tomorrow. Next, Mr. Rylander explained the lab that we will be working on today and tomorrow. In class we began to work on the first part of the lab out of three parts. The setup of the lab was that we had a domino with a ruler on top that acted like a ramp. We were to roll a marble down the ramp and see how far it would push a folded notecard. We recorded that data into our journals. Then Mr. Rylander gave us a specific number of how far he wanted the marble to travel and we had to push the notecard that distance based off the data. If you got it correct, Mr. Rylander initialed your journal. If we had time we began to work on the second part of the lab which changed the amount of dominos stacked.

Homework: Complete worksheet with practice ACT questions and start on the WebAssign.





Tuesday, December 8, 2009

Today in class we received our grades in our QOD folder, but we had no QOD today. We put in the ACT questions into our folder, and turned it in before we went back into the lab. In class we finished part 2 and part 3 of the lab, and have to finish the conclusion questions for homework. If you had two dominoes, the placement would be half of what it was with only one domino. The same goes for when you have three dominoes stacked, it is a third of the distance you had it the first time.

As the amount of dominoes needed, if let's say you had two dominoes and you started at the 7 inch mark, to get the notecard to the same spot with more dominoes, you would divide the original spot by two. Mr. Rylanderh has also started making available the review webassigns, which, will not be gigantic but rather little 15 point assignments.


Wednesday December 9, 2009
Today we learned about work. this was the main focus of the day, but first we discussed the lab, and went over parts 2 and 3. After making the discovery that the distance pushed by the card relied on the height of the marble, which explained why the double- stacked ramp required half the measure on the ruler as the single stacked ramp. this was also true of the triple stacked ramp, that it required one third of measure on the rule.

Moving into the work direction- Mr. Rylander brought out two arrows used to determine what values of work correspond to positions of arrows. A story was told about how Mr. Rylander paid a friend to move bricks, and he paid him by the amount of work he did, so his friend got nothing, because the positive work of picking up a brick is canceled by the negative work of putting it down, and the distance traveled has no work, because the force is perpendicular to the displacement.

The Webassign is up, so get to completing that as soon as you can!

Thursday December 10, 2009

​ Today we started class with a QOD . In the QOD we had to determine whether the given force did positive, negative, or no work at all. When determining this we had to think back to yesterday when we went over the different types of work.
Positive Work: When the force and displacement are in the same direction.
FORCE DISPLACEMENT
Negative Work: When the force and displacement are in opposite directions.
FORCE DISPLACEMENT
No Work: When the force and displacement are perpendicular to eachother.
FORCE DISPLACEMENT
​ Then, after the QOD we learend a few more of the basic equations we will be using in this unit, which include...

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(These two equations mean the same thing... Final kinetic energy-Initial kinetic energy)
external image latex2png.2.php?z=100&eq=W%3DKE_f-KE_i

Work * Energy Theorem
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Homework: Work on the Webassign

Friday December 11, 2009

Today we had a QOD. In this QOD we were given 4 situations and rank them from greatest amount of work to least amount of work. To solve the amount of work we used this equation.equation_111.png.

After the QOD, we learned a new equation and term for chapter 10, power. Power is defined as the rate at which you do work. The equation is power equals work divided by time, equation.png. For power, the units is watts. We saw an example of Mr. Rylander picking up up a brick two times, the first time slow and the second fast. It was the same brick, therefore the safe force, and was picked up the same height (displacement). This showed that each time the same amount of work was being performed. The difference, in which he applied this new concept power, was that one was done faster than the other. The faster one had more power than the slower one because the rate was faster.

To apply this idea, we had a competition in class to see who had the most horse power. To find horse power, you have to find your power in watts,equation.png,then convert watts to horse power (750 watts= 1hp). The plan was you had to time yourself running up two flights of stairs, 1st and second floor. Before doing that you find the height of the stairs as your displacement. The force you use in the equation equation_111.png, is your weight but converted into Newtons (4.4N=1lb). For the angle, your displacement and force are traveling in the same direction, therefore you don't need to multiply the cosine of the angle. After you collect all your data, you plug it into the power equation, then convert to horse power. The contest was to beat Mr. Rylander whose horse power was .8hp. In the end three people in the class beat him, which are the following: Vince, Nick, and Daniel.

Monday, December 14, 2009

Today we started out with a QOD. Here it is
question of the day

He then taught a lesson about potential energy and kinetic enegery. Potential engery is known as the engery of possition. Potential energy is equal to the gravitational force multiplied by the displacement.
When the potential energy is added to the kinetic energy, the end product is called Total Mechanical Energy.
Then we went and worked on a lab. In the lab we we supposwed to draw a conclusion between the three kinds of energy.

Tuesday, December 15, 2009

Today we took the first 15 minutes of class to review the lab from yesterday. We discussed patterns between potential energy, kinetic energy, and TME graphs. We learned that as kinetic energy increases, potential energy decreases and vice versa. TME means Total Mechanical Energy, which is potential energy and kinetic energy combined. Then, Mr. Rylander showed us a couple demos with a bowling ball and a mini rollercoaster. When the bowling ball wasn't moving at all, it still had some potential energy because it was at a certain height above the ground. A rollercoaster is moving the fastest at the very bottom of the hill because all of the energy is kinetic and there is no potential energy. Towards the end of class, we glued three examples of conservation of energy in our journals. We had to decide the initial kinetic energy, potential energy, and work for three situations. We also had to find the final kinetic and potential energy. The new equation we learned for conservation of energy is: PE + KE + W = PE+ KE. We ended class with a QOD relating to the conservation of energy equation.


Wednesday December 16, 2009
Today we continued are discussion on energy, as we went over questions which have to do with conservation of energy. Using the equation PE+KE+W=PE+KE. We were able to solve for m/s on any obstacle which was given with the knowledge of the original height and the initial height. Also after the marble example, Mr. Rylander explained how the weight isn’t needed to find the final or the outcome of the equation, since it’s canceled out on both sides of the equation. Since PE+KE= conservation of energy, you are able to find PE or KE with any height given. At the end of class we went over a QOD. This was the same example as the 2nd diagram Mr. Rylander has given us earlier. Since the initial height was 1m and the final height was .45m. We used the PE equation and substituted a random number for weight since it doesn’t matter. (2)(9.87m/s)(1m)=PE=19.6J. Since there was no force the KE=0. That means that the final amount has to be 19.6J. The 2nd part of the equation requires us to use the same step but with .4m. (2g)(9.8m/s)(.4)=7.84J= PE. Since PE+KE=Conservation of energy. 19.6J was subtracted from 7.84J to have an outcome of 11.76J. With this we solved backwards to find the M/S for KE.


Thursday, December 17, 2009

In class today we were in the math lab, working on Webassign questions. Here is the link to webassign: http://webassign.com/
There was no question of the day.

Homework Due 12/18/09
Webassign on Ch.10&11
study for TEST TOMORROW