Circuits 12-22-10

In class today we went onto the phet website and made a parallel circuit that also had a series circuit. Then after we made that and got Finley to look at it there were a few steps we had to take to complete the task.
1. Draw the diagram in your notebook.

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2. Identify which are in series and which are in parallel. Why.
My answer to question two was that light bulbs A, B, and C are in series because they are all connected by the same circuit. I then said that light bulb D was in parallel because it wasn’t in the same circuit but its circuit used the same batteries as the other circuit. I’m not sure about those explanations on parallel and series so if someone could comment on this than it would be helpful.
3. Describe the electron movement when it is close to fewer light bulbs and when it is close to more light bulbs.
The electron movement gets faster when it goes to the single light bulb (D) and the electrons slow down when they get close to the series of light bulbs (A, B, C).
4. Why does this happen.
I think this happens because there is less resistance when it goes to the single bulb so it can go faster, but when it goes to the multiple light bulbs there is more resistance so the electrons slowed down.
Also don’t forget that we have a quiz tomorrow!

-DB

12/20/10

Fin asked us about self controll. He asked Steve to go up and break a light bulb that he wrapped in a shirt. Steve broke it. Finley passed around the bottom part of the light bulb. Ha asked us if we could trace the path of the wires in the bulb and tell if it was important or not. When we examined it there was a spring on the top connected by 2 rods that went down through the glass that holds everything together. We had to draw what we saw in our notebooks. We also had to answer the ?s "where do the wires go" and "why is it important". We saw that the wires came out of the bulb and did not touch the bottom of the bulb. This was important because if it were to touch the bottom of the bulb, then the electricity would just circle around in one spot. The wires also go out because the electricity needs to find a way out of the bulb to go outside. Fun then passed around the bulb again to see if we could finfd evidence of the wires coming out. My group found where the wires were coming out- one on the side and one coming from the bottom. FIn asked why the wires were going in 2 different places. Then, fin brought back up the whole plastic parachute senario when he rubbed the parachute on Sasha and Yamato's head. He said that when you rubbed it on your hair, you are releasing electrons creating static electricity. He then rubbed the chute onto several people's heads and said that this realeased positive energy. Anthony said that it released electrons that traveled from the desk onto the chute then to the head. We then watched an Irish movie about electricity. In the movie they said that traffic also creates static electricity. Then they moved on to electrical circuits. They said that an electrical circuit is a circuit that makes electricity move around. They gave pictures of circuits. ON circuit, the parallel circuit, has electricity that goes around in a circle. A series circuit is where the circuit goes to more than one place at once. The movie moved on to telephone wires and that good stuff and how the high voltage can kill a person. This happens because the human body is mostly made up of water, and since water has a strong reaction to electricity, the shock can kill a person. Then they explained that a wat is equal to a jewl or newton (Fin pointed that out). THe movie moved to how electricity also creates heat and fuses. They then explained that life would be very difficult without electricity. The movie ended after that. We talked about the movie and their accents after the movie was done.
There is a test tomorrow along with a study session at 7:00- there might be donuts
:-)

WR

Energy and Circuits- P2

Today we went over our homework from Phet.com. Our homework was to create a circuit that lights a light bulb. After creating it on Phet.com, you can see how the current is passed from the battery to the bulb through the wires. In order for the current to work, you need an energy source (battery) and a place for the energy to be recieved (light bulb)with a switch to turn it on. If you have an open circuit, energy cannot be passed through.
A closed circuit is a complete circuit where the energy can be passed through in a circle.
A resistor is a tool that you can add onto your circuit which can slow down your current and dim the light.
If the circuit has a too high of a voltage, it will catch on fire.

Energy cannot pass through a dog.

Energy can pass through metal a lot easier than a non-mental object.
The blue dots that pass through the wires are the electrons. Electrons are a part of an atom. The electrons preform kinetic energy while traveling throught the wires.

Another thing we've briefly talked about was static electricity. After rubbing hair with plastic the result was that it stood up. This is caused by electrons. The electrons from the plastic was rubbed onto hair which made it stand up.


S.D

8.4 questions; December 16, 2010

Today, we went over our unit 8 questions.

8.4 a. A roller coaster pulls the cart to the top of a hill by doing 150,000 J of work on the system. The internal energy of the system changes by 50,000 J. How much more kinetic energy does the system have when the cart makes it back to the bottom of
the hill?

Remember, to get to kg from just grams, you have to divide by a thousand or move the decimal point three times to the left. Afterwards, you have to multiply kg (mass) by 10 to get the force. Once you have found what the force is, you use the formula "Force * Displacement = Work" In this case in 8.4, you have 3g. 3g divided by a thousand is 0.003. Times that by 10 to get force or 0.03. So now, force= 0.03n.

Now, in the formula Force * Displacement = Work, we haven to substitute Force in for 0.003n. Also, work is substituted for 50J. Now we can modify the equation to "Displacement = Work/Force. One J is equal to 1n * 1m.

Force * displacement = Work or Displacement = work/force
0.3n *166.667 = 50j or 166.667 = 50/0.3n
I had to skip 8.4 b so now we are on 8.4 c.

8.4 c. A meteoroid, moving with high speed, enters the Earth’s atmosphere and falls toward the Earth. As it passes through the atmosphere, it warms due to friction with the air. When it hits the ground, it creates a giant crater. Explain the process using any or all of the ideas of work and energy changes (consider all possible types of energy change). Include a work-energy bar chart.

In this problem, the system is the Meteor. We have Kinetic energy in the Initial state with work then added to equal Kinetic energy with Internal change energy in the Final state. In this problem, the earth is doing the work.


8.4 d. A skydiver who jumps out of an airplane at 3500 m above sea level accelerates towards the ground for about 15 seconds before the upward force exerted by the air on the skydiver is about equal to the downward force exerted by the Earth on the skydiver.

a. Draw a force diagram for the skydiver after she/he has been falling for about 15 seconds.

There should be Grav. pot. energy and Kinetic energy. Also, there should be negative work which equals out to less Grav Pot. energy and less Kinetic energy


b. The skydiver’s speed remains constant at 55 m/s until he or she opens the parachute. Choose the skydiver, the Earth, and the air as the system. Draw
a work-energy bar chart that describes the skydiver’s fall from when he or
she leaves the plane until just before the parachute opens.

Comment if I left anything out or messed up anything!

Class work and HW: Go to Google and search for PHET and play Sims
click on first link
go to physics
Then electricity, Magnets and circuits
then go to circuit construction kit
Create a machine that lights a light bulb and explain how it works!



Most likely there's a test Tuesday!!!
BB

December 15, 2010

We started our class with a problem. We had 3 senerios. A box being lifted by a crane, a box at the top of a frictionless surface sliding down the ramp, and a box being pushed up a frictionless ramp. A and B are the same because they have the same amount of displacement. To convert grams to kilograms you divide it by 1000 because there are 1000 grams in a kilogram. To find the force of a 20 kg object you multiply by 100 and get 200N. To get it up a 2m high ramp it takes 400J because you have to multiply by the hight of the ramp,(2m.)by the force it takes to move the object
(200N). The differnce between force and work is it takes alot of muscle to exert force and no work can be done.
A.M.

December 14 ,2010 - Starting to Going Over Lesson 8

Today in class we started by finishing watching Mythbusters.
After we finished watching the video, we went over lesson 8.
8.1 a) We said that the Americans With Disabilities Act is concerned with the steepness of accessibility ramps because there shouldn't be too much force (not work) needed to go up the ramps. It isn't about work because the amount of work stays the same no matter how steep the ramp is. This is because when the ramp becomes less steep, there is less force but the distance increases.
b) since the ratio for the height and width of the ramp was 1:12, I said that possible ramps are 3m by 36m, 5m by 60m, and 12m by 114m.
c)I said that ramp "iii" fits the requirement.
In class we learned that you can find how much force needs to be applied to something by doing (Mass * 10). This is only true with kilograms so if it is in any other units, it must be converted into kilograms.
d)
i) To find out how much work is done on that ramp, we needed to know that Force * Displacement = Work. Using this rule, Mass * 10 = Force, we found out that we would need to apply 200N. The height of the ramp was 2meters so the displacement is 2m. By doing 200N * 2, we found out that it would take us 400J of work to push a wheelchair up the ramp.
Class ended so we did not go over the rest of problem d)

I was still confused about why we take the height of the ramp for displacement and not how much you traveled/moved the wheelchair

-AT

Decmber 10, 2010 Period 2

We had a sub today, so nothing really happened. We worked on section 8 in the energy activites packet and we have to finish it for homework.
http://www.npsd.k12.nj.us/20222069133223760/blank/browse.asp?A=383&BMDRN=2000&BCOB=0&C=59194 here is the link to the page for Energy Activities. Its on the bottom of the page.
GS

energy activity sheet

Today in class when we went over the energy Activity Sheet we had for homework. For the first problem The number sentence was 3J +2J=5J. My initial state was You're falling down a mountain(halfway down) and my final state was you're moving really fast at the bottom of the mountain. On my bar chart i had 3J for kinetic energy and 2J for gravitational potential energy (before side) and 5J for kinetic energy on the after side.

The second problem's number sentence was 4J+(-2)=1+1. My initial state was a cart coming toward me and then i pushed it away from me and its about to fall off . My final state was The cart is falling down the mountain about to hit the ground. For my bar chart, i put 4j of energy for gravitational potential energy and -2 work being done(before side). I put 1J for kinetic energy and 1J for gravitational on the after side.

The third problem's number sentence was 200J+800J=500J+500J.My initial state was you jump off a cliff, moving fast,you're 4/5 of the way down.The Final state is you're half way down, moving fast. For my bar chart, i put 200J for kinetic energy and 800j for gravitational potenial energy (before side). Then i put 500J for kinetic energy and 500J for gravitational energy on the after side.

AR

towards the end of class Mr.Finley asked the question why does a pendulum swing back to its original height? Clarie answered that its because nothing does work. She also mentioned that when the pendulum reaches its highest point it has the same amount of energy it started with.

Tuesdays Blog

At the beginning of class, I asked a question about what constant and conserved energy was. Mr.Finley said that consistant energy was when the amount of energy does not change, but the type of energy changed. Conserved energy is when energy changes in a predictable way. The quiz tommorow will be on bar charts, number sentences, and energy. He said to just remember how to make bar charts.Mr. Finley told us to discuss about a problem where a box went from the ground to high up in the air. He said to say which process will require the most amount of energy. A crane lifting the box, a person pushing the box on a slanted board, or a person pushing it on a spiral staircase. We said that the spiral stair case will require the most energy. we had to draw a bar chart for all of the sceneareos. Mr. Finley said all of the situations started out with no energy. It turns out that all of them had the same amount of energy at the end. They all had the same amount of work as well. We discussed why we might want a spiral stair case. We said that the spiral the 50J of energy will be used in a longer amount of time, makeing it easier. For the crane, it is a short distance, but it will be much harder to lift it straight up. We discussed that a pengulem would be dropped at a height. Where would it be on the other side. We also said to say what would happen if there was a bar in the way. We said that the pengulem will go the same height as it was before. If there was a bar in the way, we said that it will go half of what it would normally go. Remember to study!

MP

Monday, December 6th: Skateboard Problem

Today, in class, I began working on the skateboard problem. For the skateboard problem, the first part is to design a skate park for the skater to skate on. After a few minutes of designing, I designed a skate park like this:

Afterwards, I had to answer a few questions about the skater/skatepark. Here are my questions and answers:

a) Draw a picture of your track.

(shown above.)

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Place the skateboarder on the track and observe the motion. You can investigate further by changing the skate or you can scroll down and adjust the fiction. Choose two different situations from the simulation that you can analyze and then share with the class.

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1. My first situation is on Earth, with the PhET skater. The track is my original track shown above, and the friction is none. I observed that the skater keeps on going at a consistent speed and it pauses for the same amount of time when it reaches the ends of the track every single time.

2. My second situation was using a bulldog on the Moon. The track is still my original track, but the friction is medium. I observed that the bulldog wasn't able to move as fast; in fact it couldn't even go through the loop because of the friction. Things on the moon are supposed to be lighter, so friction can really slow someone down.

b) Describe or draw your chosen initial and final states

initial final

c) Include your choice of a systems

My choice of the system is the Earth and the skater.

d) Create three different representations (i.e. picture, bar chart, force/motion diagrams, number statement, graphs, etc) to demonstrate the changes that occurred during the process.

40J + 20J = 20J + 40J

e) Is the skateboarding situation realistic in terms of the physics and energy?

Yes, because the more friction there is, the harder it is to move in real life. Not any of the things programmed into this game have violated the laws of physics.

That is about all we did in class today. If this wasn't finished in class, it was finished for homework.

- J.L.

Friday, December 3 - HW Review & Elephant Project

Today we went over the homework and had a class disscussion. The homework was to make problems that related to the 3 number statements given. You also had to describe the proccesses of energy conservation and the constant processes. Last, you had to draw a bar chart and solve the problem. When we went over the homework as a class, and we realized how to follow the number statements that were given to us and accurately make a problem that relates to it without stating what happens prior to what you're given.

Then, we went back with our groups to work on the elephant project. We started the elephant project two days ago when we watched a video to start us off. The video was about an elephant that steps onto a trampoline. It shows the elephant walking up the steps, and starting to jump on the trampoline and jumping on it. Mr. Finley gave us a task to find 5 things that related to energy from the video, draw the intial and final states, bar charts, and number sentences. There was also an additional question which is: "Is the elephant situation realistic in terms of physics and energy?

You can watch the video at:

http://www.youtube.com/watch?v=TK27aknWVI4.


A.L.

Today we worked on the elephant promblem. In the elephant problem we saw a elephant jump on a trampolene and do flip. He asked us 5 questions. 1. Write about 5 different things in the video that relate to energy. We said walking to climbing stairs. Stairs to trampoline. standing on trampoline to jumping on it. At the peak of height falling. From trampoline to walking. 2. Describe or draw intial and final states. 3. Include your choose of system. We said The elephant, trampoline, and earth. 4. Create three diffrent representation( picture, bar chart, number statement.) to demonstrate the changes that occured during the process.5. Is the elephant situation realistic in terms of the physics and energy? Explain.
If you want to see the video go to youtube.com and type in elephant jumping on trampoline
Then we went to a website(colorado.edu) and played a game energy skate park. It was a person on a ramp going back and fourth.

-MM

Energy Bar Charts and Project

Today we first started to work on our bar chart packets. They have to be done by today, or you have to come in during study hall or homeroom. If you were absent, then check with your group to get the answers.

Then, Mr. Finley called up our groups to check our homework, the bar charts for the skier problem and lifting a ball problem.

To check this we are going up to Mr. Finley computer with our groups. We are to view two PowerPoints with all of the answers on it, and compare our answers. This will be available tomorrow as well, so don't worry if you didn't get to it.

Then we were called up to the front by groups to be told about a project. We have to watch a video about an elephant jumping on a trampoline, see 5 thing in the video that relate to energy, and choose 2 that you can analyze and share in class. We have to draw or describe initial and final states. Then we have to include your choice of a system. Third, we have to create three different representations that show the changes of energy that occurred. You can use a picture, bar chart, number statement, descriptions, etc. Finally we have to answer if the the elephant situation is realistic in terms of physics and energy. Remember, this is a group project. You don't need to start it at home.

Here is the video:

Tonight's homework is:

Nothing as of 4:30. As we all know, Mr. Finley posts homework by 4:00 so it is safe to day there is no homework.

Here is the webpage

I am somewhat confused about what the difference between energy conservation and energy constant. Can somebody clear up what these two terms mean and how they are different?

Thanks!

MK

November 30, 2010

Today in class, the first thing we had to finish up was to go over the ski problems and to make sure that you made the bar charts for it. Bar charts should look like this.

Rasing the Bar packet must be done and you should almost be done with the Energy packet.

You also have to go over the homework that is due today and start making bar charts for all of the problems.

Energy Packet

1. The first problem was that Jessica stands on the 1st floor of the elevator. The door closes and she goes up to the 4th floor. Jessica and earth are in the system.

a.) Jessica, Earth, and Elevator

b.) Initial is when she is on the 1st floor. Final is when she is on the 4th floor.

c.) Creat own work-energy bar chart

2. Alan's Solution

a.) We agree with Alan and his charts are correct and so are his answers.

b.) The chart helps him see the changes from start to end and the amount of work done.

c.) They show the amount of work and energy in the system.

d.) He found out that displacement * force = work and he found the lengths of the bars.

3. 4.5 Reason

a.) The work and the final energy would be split in half.

b.) She would still have GP energy but less than if at the top. She would not have kinetic because the elevator moves at a constant rate.

c.) 0+1000J=1000J

That's all we got done in class.

-Yam

Class on 11/24

In the beginning of class, he told us that:

we are going to start a group project on Tuesday. The bar chart packet must be done by then.

We had everyone break up into their groups as usual, and the "skier people" looked at a PowerPoint presentation on his laptop, and we need to remember some of it for the homework.

The homework for the "elevator problem people" is to do the skier problem, and for the people like my group, "the skier problem people" is to correct and explain any mistakes you made using the PowerPoint presentation that we looked at in class.

I have a question for everyone out there: for the system for the skier problem, why is the mountain not in the system?

And, if you don't get how to make bar charts for the skier, I have a hint; he tells you what the system is in one of the old hws, and those are labels. Here's what the old hw was:

-MA

11-23-10 Elevator problem

We started out in class with going over the blogging rules:

• You must comment twice a month


• November and December are going to be combined, so you have enough time to make your tow comments.
  
• The comments should be either a question or correction.


• Answering a question counts as a comment.


• Your comment should be on a recent blog, otherwise no one will see it and respond.
  

The picture is what a bar graph would look like.

Next we began to work on a few problems with the bar graph packet.

It was: $20 in your wallet, $60 int he bank, and $20 pocket.

If you take $20 out of the bank, and put it in your pocket what would the bar graph look like now.

We would then draw a picture of the change. This is what the rest of the bar graph packet was like.

Then we got into groups, mine was going over the elevator problem.


Say the elevator is 1000 N and Mary is 100 N the weight now is 1100 N the elevator height is 10 meters, how can you figure out how much work was done?


Force* displacement=work


1100* 20= 22000 J

We got 1100 form the weight of Mary and the elevator, and we got 20 because we drew a picture to help us figure out how much distance the elevator would have to go..


Next we had to figure it out if Marys twin sister was on it, we assume she weighs the same.
Mary is 100 pounds, and her twin is 100 pounds

1200*20= 24000

N=Force
Meters= displacement

If we went on the elevator for 4 floors instead of 3, it would be:

1100*30= 33000

1100 because of the weight of the elevator and Mary, and 30 because of the amount of meters between the floor of the first floor and third.

Something I am a little bit confused on is how to make an integer statement. If anyone wants to comment and tell me how, that would be good.

KK

Bar Charts

Thursday, November 18

We started the class by going over the homwork.

The homework problem was:
Eugenia slowly lifts a box by exerting a constant force of 5n. She moves the box from the ground up onto the table, which is 1m high.

Here are the questions on the homework:
1. Draw a picture of intial and final state for the box while she is lifting it.

2. Calculate the work Eugenia has to do in order to lift the box onto the table.

3. Dicuss the energy transformation and write a number sentence to express what occured.

4. Suppose Exerted a larger amount of force on the box at the beginning. What would she have to do to get the box to stop when it got to the table?

We also discussed this question:
Mary rides in an elevator from the first floor to the third floor. Answer the following questions.

Here are the questins:
1. Sketch the intial and final states, and then identify the system.

2. Make a reasonable approximation for the force applied and the distance between the floors in the building.

3. Write an integer statement for the work the elevator does to lift mary to the 3rd floor. Find the work.

4. How much work would the elevator have to do if marys twin sister joined her?

5. How much work would the elevator have to do if mary decided to go to the 4th floor instead? (find the work for both cases: with and without her sister)

-SA

November 17th Wednesday Period 2 (Spring Story)

We started by discussing the homework. We had to describe changes in energy in a story.

1. The spring is pushed down

2. then its released and shoots

3. then it stops going upward and is in midair.

4. it next starts to drop

5. lastly it is caught

On the white boards we wrote the energy transfers for each step and discussed it as a group.

1. We agreed that there was positive work done that transfered it from no energy to elastic potential energy.

2. For this one the spring changed from elastic potential energy to kinetic energy.

3. No the spring loses all of its kinetic energy but has gravitational potentioal energy.

4. The spring loses gravitational potentioal and does downward gaining kinetic energy.

5. Finally the spring is caught where there is negative work aplied to the spring to make ot stop.

We next lodoked at a table with various amounts of force, displacement an work.

We instantly saw that the force times the displacement equals work. Mr. Finley then told us to think of what negative work is. Many groups came up with the idea that negative work is the opposite of work such as negative kinetic energy would be slowing something down or stopping it.

-JP

Period 2 Energy and Systems

Today we are going over the types of energy (gravitational potential, elastic potential, internal, kinetic). We are figuring out what work is being done to these situations:


Person dragged along the ground --> work: thing that is dragging the person
INTERNAL ENERGY system: person, ground, earth

0 J + 5 J = 5 J (started with no energy and gained 5 J of energy)

The ground needs to be in the system because it causes friction on the ground to heat it up. The earth also has to be in the sytem.

Hot air balloon rising into the air --> work: hot air or fire GRAVITATIONAL
system: earth, balloon POTENTIAL

50 J + 10 J (started in the air and increased height by 10 J)

Person on a pogo stick --> work: earth, pogo stick
system: pogo stick ELASTIC ENERGY

I'm not sure about this one but i think it would be: 5 J + 5 J = 10 J because you bounce up and down each time it is not like going down a hill and increasing energy.

You need to have the pogo stick in the system because it wouldnt have springiness (elastic energy) without it.

Car falls off of a cliff --> work: earth system: car KINETIC ENERGY

10 J (driving) + -5 J (falling negative work) = 5 J

I am a little confused on how you would find the equation for something like the pogo stick problem so can anyone tell me what they think it would be? Thanks

EE

11/12/10

First, we went over a few things from yesterday that we didn't get to. We first talked about the homework from a few days ago having to do with the cart on the ramp. The whole process was as follows:

First, the spring sprang the car to the edge of the ramp.

Then, the cart fell off the ramp.

Next, we went over last night's homework. As a group, we had to write our idea of an example of the following: Positive work that causes an increase in the elastic potential of the system. We had these ideas:

---Slinghot Number Sentence: 5+4=9

---Treadmill Number Sentence: 5+4=9

---Rubber band Number Sentence: 5+4=9

Mr. Finley's: Kinetic to Elastic

System: Person, Trampoline

His situation: A person speeding down very fast onto a trampoline that stretches.

20 Jewels= 20 Jewels

Jewels: A unit for energy

JP table idea: Gravitational potential energy in the system is converted to internal energy

A rock is pulled down on a rubber band.

System: Rubberband, Person, Rock

gravity+ -2 gravity+ 2 elastic= 2 elastic

MP table idea: Positive work to kinetic energy

Person pushing a cart

0 units+ 2 units

System= Surface where cart is pushed

DB table idea: Positve work to gravitational energy of the system

A ball falling off of a table

Couldn't come up with an equation

System: Ball

AL table idea: Gravitational potential energy in the system is converted to internal energy.

When meteorites get pulled to earth, they warm up as they go through the atmoshpere.

5 unites of energy+0 units of energy= 5 units of converted energy.

The earth/atmosphere does the work

JF table: Kinetic coverted to grav. potential energy

A kid climbing up a diving board ladder but not jumping up

3+2 +-5+6=6

System: Diving board, Ladder, Earth

This is important because it is the basic facts of this unit. We are going to have to build on all of these different types of energy, so it is a good thing that we are getting familiar with all of them.

Website

EC

Today in class we talked about the five different types of energy. The five of energy are:

• Nuclear Energy
• Light Energy
• Mechanical Energy
• Electrical Energy
• Chemical Energy

We specifically talked about how these types of energy can transform into different types of energy. For example, a crank radio changes mechanical energy into electric energy. The mechanical energy is when you turn the crank and the electric energy is when the radio turns on and finds radio waves and then projects the sound out of itself.
Next in class we talked about the types of mechanical energy which were:

• Kinetic Energy
• Internal Energy
• Gravitational Potential Energy
• Elastic Potential Energy

We then reviewed our homework from Monday and in the first four questions we switched our made names for the situations and inserted the scientific names. The answers were:

a) The external force caused the block to move higher above the Earth’s surface.
Gravitational Potential Energy
b) The external force caused the cart to move faster and faster.
Kinetic Energy
c) The external force caused the slingshot to stretch.
Elastic Energy
d) The external force caused the surfaces of the touching objects to warm.
Internal Energy

During the discussion about those questions we decided that Gravitational Potential Energy meant that gravity had a chance to pull it down to the ground. We also found out that Kinetic Energy was the speeding up of an object not the moving of an object. If you have trouble with this concept just think of when Doc. Fin pushed MK across the room and that it was only Kinetic Energy when MK was being pushed because once Doc. Fin let go negative force was starting to be applied.

Then we answered the first 2 questions of the next section.

Examine the picture to the left. One of your classmates says, “When the car gets to the edge it will have ‘the ability to fall’ or ‘falling ability.’”

a) If the Earth weren’t there, would the car still have “falling ability?” Explain.

b) Should we include or exclude the Earth with the car when we analyze this problem?

For the first question we said that if the Earth wasn’t there than the car wouldn’t have falling ability because the Gravitational Potential Energy that affected the car would be gone. The next question’s answer is that we should include the Earth with the car when we analyze the problem because our results from the previous question show that the Earth is what gives the car falling ability.

Lastly before the bell rang we discovered that every mass has a gravitational pull these masses could be as big as the earth or a small as a chair.

-DB

November 8th, 2010 -Energy Reminders For Test

Today we made a list in our groups to remind us what we know about energy; here's the list. We all tried to remember stuff and we didn't know if its right or wrong. Yet.

Energy

• No mass


• Many forms of energy


• Can never be destroyed


• It never stops going

Then we came together as a class to see what we all came up with;

Brady's Group:

• Light is energy


• Energy cannot die


• You can apply energy


• You can't apply energy to yourself

And a few more.

Yamato's Group:

• Energy has no mass


• Not a state of matter


• Many types of energy


• Can be transferred object to object


• Can be transferred by applying force.

Steven's Group:

• Work is transferring energy to or from our object or system by applying force and having our object displace


• Force; push/pull


• Displacement; change in position

My group:

See the first list.

Alexia's group:

• Isn't matter


• Transferring energy to an item is work


• Doesn't always displace


• Need energy to have chalk smashing ability


• Types of energy; microwaves, UV rays, gamma rays, x-rays.

JayGee(:

**Remember we have a test tomorrow and there's a study session at 7 tomorrow. Study!**

November 3rd, 2010

We didn't do anything, we just went over the homework and played a review game. Have a good four day weekend!!!!!

JG

Chalksmashing Ability

First we went over the homework. To give a big book chalk smashing abillity is to pick up the book first. Force is push or pull. Steven is pulling the book upward. The displacement of the book is upward. When the book is risen upward it is given chalksmashing abillity because the displacement and the force are going in the same direction. When the book is just lying on the counter it does not have chalksmashing abillity because there is no chalksmashing ability. For a cart to smash the chalk it has to be pushed toward the chalk to give it the chalk smashing abillity. When the sling shot is pulled back and the dispacment is backwarsds. A pattern is that went the force and the displacement are going in the same direction. But when the force and the displacement are not going in the same direction it does not have chalksmashing abillity. When Josh pushes a cart and Jenna stops it it gives the cart no chalk smashing abillity. Before Jenna touched the cart the displacement was going to the left and when jenna started to push the force went in the other direction it lost it's chalksmashing abillity because the force and the displacement are going in differnt directions, But when the force and displacement are in opposite directions it loses chalk smashing ability. When we do things to the book and the cart we are transfuring energey to the object by applying force and causing displacement. The reason why we can't pick each other up is That we cant transfer energy to ourselves.
-Anthony M.

Light Review/Chalk experiment

Today in class, we started by checking our homework from last Friday and from the weekend. We were suppose to play a review game using the questions we came up with, but many of the questions where not what the teacher was expecting.

Than we decided to go over the discovery of Newton.

The question based on Newton were:
What happens when white light goes through a prism?

People answered that white light would spread in the prism as it bends and since white light is made up of many colors, when it slows down in the prism, many colors appear.

We discussed about how the different colors have different speed and bend more or less


Than we discussed why this doesn't happen with laser
We thought that this happens because the light of the laser is not white but red.

Next we thought about why do we see the object's color? (why is the sweater orange and why is that sweater blue?)
Light hits the object and goes into your eye,
when the white light hits the orange sweater, only the orange light bounces off and other colors get absorbed
We thought about the time we were observing the laser and thought about how when the laser is shined at a black poster, the laser becomes less visible than when we shine it on an orange poster.

We could test the absorption by placing a black colored paper and a white color paper under a glass of water and see what the temperature of the water is.


Than we asked our selves, where do we see the prism effect in real life?
After rain we would see a rainbow we would see the prism and white light effect. This happens because the sun acts as the white light and the moisture in the air would act like a prism and bends the white light

What are the other types of energy?
white light
UV rays
microwaves
x-rays
inferred

Towards the end of class, we placed a piece of chalk under a dictionary and we thought about what would we have to do in order to smash the piece of chalk using the dictionary.

We said that if we drop a book from a distance, the chalk would break. The dictionary would be more able to smash the chalk when it is farther away from the chalk. One student stood on a chair and dropped the book and the chalk did smash

by AT

Cow Eye Dissection

This is my blog for dissecting cow eyes .My partner and I are taking it apart step by step. CS

10/28 Period 2

We started off by going over the homework, then we tested to see if the laser can split like in the game. It doesn't split the same way in real life, it was more of a flashlight.



Then we went over how a laser reflects and refracts in a triangular prism, and how a flashlight makes a rainbow when it goes through a prism. We went over what a rainbow was and how white light bent to create one. Certian colors of light slow down more than others so that they seperate and turn into the rainbow. When a second prism is held up to the rainbow it becomes white light again. We saw Newton's model of light going through a prism.

http://www.buzzle.com/articles/color-spectrum-chart.html her is an article with a picture of Newtons theory. GS

Period 2 Triangular Prism Experiment

Today we continued to do the triangular prism experiment we started yesterday.

For the first activity,you have to shine the laser through the triangular prism, you must include:

• a prediction
• test observations/drawing about what you saw
• conclusion

My group's prediction was the light will reflect off everywhere. During our testing, we observed the light went everywhere. Laser beams were everywhere you looked. We concluded the light refracted and reflected off the sides of the prism.

For the second activity, you have to shine a flashlight through the triangular prism, you must include:

• observations
• describe what you saw(facts)
• draw a picture that explains what you saw
• Explain why the thing you saw happens
• Relate it to something(analogy)

My group and I observed that it makes a rainbow.The order of the colors were red,orange,yellow, green,blue, and purple. We also saw shapes on the sides of the triangular prism such as triangles, trapezoid.etc. We described that when shining the flashlight through the triangular prism the light goes to the opposite side of the flashlight and drew how the light rays go through the triangular prism. We explained that the rainbow can be seen because speed changes causing light waves to change causing colors to form. We related this to a rainbow forming after a rainstorm because it goes through same concept. The light goes through raindrops causing the colors of the spectrum to be formed.

To learn more about a rainbow and how its formed go to this website:

http://www.cs.dartmouth.edu/farid/sciencekids/rainbow.html

AR

Today we started out with Finley asking a question, "what would happen if light were to pass through a cube of water, a cube of glass, or a cube of helium?" We had to work and find out what would happen with our groups. After time was up, Fin asked 3 people to go up to the white board and draw out their ideas about the light passing through their assigned cube. The 3 people then sat down and waited for Fin's observation on their drawings. Fin asked other people to explain the drawings, and Fin said that they were all correct. Then he asked why the glass and the water was different. People said that the glass is more dense that water; when it's more dense, it moves toward the normal line. Then, people tried to explain the helium. JP drew that helium is less dense, so the light moves away from the normal line. After the explanations were done, Fin gave us 3 activities. First, he said we were going to experiment wth triangular prisms. We had a normal lazer pointer and a flash light. We had to shine the lights in all directions around the light. But with the flash light, he wanted to shine the flash light going down towards the triangle. We had to obsereve, describe, draw, explain and relate. In the drawings, he wants all the light rays coming out the flash light pic. Finally, we had to take a pen/pencil and put it in a pitcher of water, and draw a pic. of why the ruler was closer; that part was bonus. We then broke into our groups and started the experiment. Right when we start, the fire alarm goes off. The drill only took 3 minutes and we came back in and finally started to work. In my group, we predicted that when we shine the lazer from the top, the lazer will reflect off the sides, and come out the top. When we tested the lazer, our prediction was correct that the lazer would reflect back up, but there were numerous other lazers reflecting out of the triangle. We did a few more tests and recorded our observations. Then the period was over, handed in our materials, and left the room.

WR

We reviewed our hypothesis that light slows down at more dense objects.We also had the hypothesis that light goes towards the normal line when it slows down. We had to talk to our group about our hypothesis. My group(Emily, Claire, Anthony, and I) decided that it will slow down if it goes from a less dense to a more dense material. It was confusing deciding how to test to see if we were right. We concluded that we will take something like water and put a more dense object under it. We will use a protractor to see the angles that they come and go at. Jermey made a good point when he said we should point the laser at the wall with nothing in its way(on an angle), and then put a prism in its way and see how much it bent. I believe that this will be a very good representation for this. We decided to do the experiment multiple times to make sure we have an accurate conclusion. I liked this idea because it will give us an accurate responce. We used a metal rod to keep the laser pointer in place. Then, we marked where the laser was pointing. We then put the prism in its way. We saw it move differently when we move the prism. I think this experiment was a lot easier to set it up and do than I thought. Two points reflected off the prism as well. Only one was on the other side. It went about an inche away from the normal dot. This data supports our hypothesis.

MP

Friday, October 22nd

Our hypothesis from yesterday was that light moves slower in a denser area and faster in a less dense area. We also hypothesized that light is more stretched out when it is fast and it is more condensed when it is slower.

Next, we reviewed the homework from last night. The homework from last night was:

"Construct a prediction of what would happen to a slinky when it moves from a less dense area to a denser area. Then watch the video and say if your hypothesis supports

your prediction."

The video was of a slinky that had 2 parts to it. Half of it was made of a thicker material and the other part was a l

ighter mate

rial. There was a person on both ends of the slinky. First, a person on the right side shook the slinky and the ripple started off very fast, but once it reached the thicker part of the slinky, it slowed down and the ripples became more condensed.

Our prediction was that when the slinky starts off in the less dense area, it should start off straight and then have light, stretched out, ripples. Then when it gets to the denser area, the ripples in the slinky would be more condensed.

The results from the video supported my hypothesis so I may conclude that light travels slower in dense areas and it travels faster in less denser areas. When light travels faster, its waves are more stretched out and when it travels slower, its waves are more condensed.

-J.L.

Friday, October 22nd

Today in science class, we reviewed what we did yesterday first. We discussed the wave model with the slinky and how it moved (the slinky represented light).

fast- more distance

slow- less distance

When light moves faster, it's more stretched out and when it moves slower, it's more condensed.

October 21, 2010

Our hypothesis from yesterday was to answer why light bends. We realized that it bends because the light slows down. Another was our hypothesis from the homework from last night. It was asking how light will bend when it goes from less dense to more dense and more dense to less dense. In class today, we discovered the light will bend towards the normal line when it goes from more density to less density. When it is less to more, the light will slow down and it will bend towards the normal line.

In class, we also observed a container full of water, with playing cards taped to the sides. The bottom had a card, but from above looking down into the container you could see it. When you bend down and look from the side, it was not seen. The 3 of 4 sides had cards too. 2 sides had 2 cards, and 1 side only had 1. When you looked at 2 of the cards, you could only see 1/2 of it at some angles, but looking from the outside, the whole card was visible. You also couldn't see the cards from the outside, on the opposite side of the container.

After that observation was finished, we discovered the meaning of photon. Photon is the 2 ways that light can act. The first way is when light bounces off of a surface. This is called reflection. The other way, refraction, is when light bends. The Particle of Light is another meaning for reflection. It is like when we discovered the mirror experiment last week. The Wave Model of Light is also like refraction. This is the relation of when light slows down or speeds up.

We decided to make the Wave Model. So, we took a long, spring-like slinky and swung it, It looked like this (I could not find a good picture, but this is what was closest):

1 wave =

Refraction:

FAST: If light speeds up, it will look like this:

The wave legnths are closer together.

SLOW: If the light slows down, it will look like this:

The wave legnths are further apart.

Hypothesis of the day: Light moves through its speed and changes.

-A.L.