Hey everyone!
In Math, we have been learning about fractions, decimals, and percents as I have mentioned in past my posts. But, how does all this come into play in our real lives? Well, it is actually very relevant, especially decimals and percents.
For example, let's say we're going shopping. We are at the CD store, and there are two CDs we are deciding between, let's say the David Cook CD and the David Archuleta CD. The DC CD is originally $25, but you get 15% off. The DA CD is originally $30, but you get 25% off. Which one is cheaper?
Well, it would look like the David Archuleta CD is cheaper, as you get 10% more off. But let's see how that turns out when you calculate it.
For the DC CD:
15% is equal to 0.15. So when you multiply $25 by 0.15 we should get what 15% of $25 is. That comes out to $3.75. Then we subtract $3.75 from $25 to get $21.25, our new price.
For the DA CD:
25% is equal to 0.25. So when you multiply $30 by 0.25 we should get what 25% of $30 is. That comes out to $7.50. Then we subtract $7.50 from $30 to get $22.50, our new price.
We just figured out that the DC CD is cheaper than the DA CD by $1.25.
So then what CD do we buy? The David Archuleta one, obviously! David Cook isn't even worth $21.25. ;-)
Percents and decimals also come in handy when calculating things such as tax on an item, how much tip to give you server at a restaurant, and many more. So, this was a very useful unit to learn, as it will definitely become relevant in our lives.
Until next Wednesday,
-K
Wednesday, January 28, 2009
Wednesday, January 21, 2009
Lots and Lots of Science in FE8B
Hey
So, we learned about our summative in Science. I was right, we are making a hydraulic system. What we have to do is transport 4 cans of toxic liquid from a factory onto the back of a truck. I know this sounds impossible, but we are actually just moving 4 film canisters of water from one side of a desk to a cardboard truck Mr. Foster made on the other side. However, we can't touch the canisters, we have to be well away from the "toxic" area, and just use controls to move the canisters. We can use either hydraulic systems (liquids) or pneumatic systems (gases). Yesterday, we did a workshop to give us an introduction on how these systems work.
First, what we had to do was take two 20mL syringes and attach them with 5 cm of plastic tubing. Then, we put the plunger on one syringe at 20mL (all the way open) and the other plunger all the way down. Then we pushed on the syringe that was open and observed what happened. The other plunger was pushed out to about the 19.5mL mark. I think the reason that the plunger wasn't pushed out exactly the same amount is because the air in the tube was compressed a bit before it exerted the force on the plunger, therefore taking up a lesser volume, but I'm not sure about that.
Next, we set one plunger at 20mL and the other completely in. We pushed as hard as we could on the plunger that was out, but then held the other in place so that it couldn't move. We could push the plunger in to the 5mL mark before the tube connecting the two syringes fell off. This is because the air compressed, but I guess it only could to a certain point and then found a way out of the container, as compressed fluids are always trying to do.
Then, we repeated the two experiments but had a 50cm piece of tubing connecting the syringes instead of 5cm. We had the same results for the first experiment. But, for the second we could press the plunger all the way in. I think this is because there were more particles and a certain amount of force, so there was less pressure than fewer particles and the same amount of force. However, this could have also been because we had different people pushing the plunger in and prevent the other from moving, so something may have varied with that. This could have skewed our results.
We then filled our system with water, and went back to using a 5cm tube. When we pushed on the one plunger, it moved the other plunger exactly the same distance. I guess this is because water is incompressible, so no force was lost compressing it. When we prevented the other plunger from moving, nothing happened; we couldn't push the plunger in. This is because water is incompressible, so we couldn't push the particles together.
The final thing we did was put one 20mL syringe at one end of the system, and a 10mL syringe at the other. We put the plunger in the 10mL syringe out all the way and pushed the 20mL syringe's plunger in all the way. When the system had air in it, the plunger on the 20mL syringe moved out a shorter distance. But, that was just an illusion because it actually moved the same volume of air we pushed in (10mL) but on the larger syringe, it didn't look like it because it was a shorter distance on the syringe scale. This was because the 20mL syringe was wider than the 10mL one. When we did the same thing except with water in the system, the results were the same.
So, that is what we have been doing in Science. I can't wait for our summative - I'm quite excited about it!
Until next Wednesday,
-K
So, we learned about our summative in Science. I was right, we are making a hydraulic system. What we have to do is transport 4 cans of toxic liquid from a factory onto the back of a truck. I know this sounds impossible, but we are actually just moving 4 film canisters of water from one side of a desk to a cardboard truck Mr. Foster made on the other side. However, we can't touch the canisters, we have to be well away from the "toxic" area, and just use controls to move the canisters. We can use either hydraulic systems (liquids) or pneumatic systems (gases). Yesterday, we did a workshop to give us an introduction on how these systems work.
First, what we had to do was take two 20mL syringes and attach them with 5 cm of plastic tubing. Then, we put the plunger on one syringe at 20mL (all the way open) and the other plunger all the way down. Then we pushed on the syringe that was open and observed what happened. The other plunger was pushed out to about the 19.5mL mark. I think the reason that the plunger wasn't pushed out exactly the same amount is because the air in the tube was compressed a bit before it exerted the force on the plunger, therefore taking up a lesser volume, but I'm not sure about that.
Next, we set one plunger at 20mL and the other completely in. We pushed as hard as we could on the plunger that was out, but then held the other in place so that it couldn't move. We could push the plunger in to the 5mL mark before the tube connecting the two syringes fell off. This is because the air compressed, but I guess it only could to a certain point and then found a way out of the container, as compressed fluids are always trying to do.
Then, we repeated the two experiments but had a 50cm piece of tubing connecting the syringes instead of 5cm. We had the same results for the first experiment. But, for the second we could press the plunger all the way in. I think this is because there were more particles and a certain amount of force, so there was less pressure than fewer particles and the same amount of force. However, this could have also been because we had different people pushing the plunger in and prevent the other from moving, so something may have varied with that. This could have skewed our results.
We then filled our system with water, and went back to using a 5cm tube. When we pushed on the one plunger, it moved the other plunger exactly the same distance. I guess this is because water is incompressible, so no force was lost compressing it. When we prevented the other plunger from moving, nothing happened; we couldn't push the plunger in. This is because water is incompressible, so we couldn't push the particles together.
The final thing we did was put one 20mL syringe at one end of the system, and a 10mL syringe at the other. We put the plunger in the 10mL syringe out all the way and pushed the 20mL syringe's plunger in all the way. When the system had air in it, the plunger on the 20mL syringe moved out a shorter distance. But, that was just an illusion because it actually moved the same volume of air we pushed in (10mL) but on the larger syringe, it didn't look like it because it was a shorter distance on the syringe scale. This was because the 20mL syringe was wider than the 10mL one. When we did the same thing except with water in the system, the results were the same.
So, that is what we have been doing in Science. I can't wait for our summative - I'm quite excited about it!
Until next Wednesday,
-K
Sunday, January 18, 2009
Science and Math - FE8A
Hey everyone!
Science
This week in science we watched two Bill Nye movies covering Friction (the force of rubbing, often transferred into heat) and Simple Machines (covered in earlier posts). Both of these topics will applied in our in our summative. Our summative will be mostly on our fluids unit that is what we have been studying for the last few weeks. Like Katie said in her last blog it must be something dealing with hydraulics.
Math
Currently in math the class was taught how to add and subtract fractions. For adding and subtracting you need to find a common denominator and then proceed to adding/subtracting the fractions. To find a common denominator, you sometimes need to multiply both the numerator and denominator of the fraction you wish to change to make it the correct number. For example, 2/10 + 2/5. You need to multiply the top and the bottom of the second fraction to get the denominator of 2/5 to be 10. Once you've multiplied by the correct number to get the same denominator, you can go ahead and add the fractions. Ex. 2/10 + 2/5 -> 2/10 + (2/5)x2 -> 2/10 + 4/10 = 6/10
Until next time,
~Eric
Science
This week in science we watched two Bill Nye movies covering Friction (the force of rubbing, often transferred into heat) and Simple Machines (covered in earlier posts). Both of these topics will applied in our in our summative. Our summative will be mostly on our fluids unit that is what we have been studying for the last few weeks. Like Katie said in her last blog it must be something dealing with hydraulics.
Math
Currently in math the class was taught how to add and subtract fractions. For adding and subtracting you need to find a common denominator and then proceed to adding/subtracting the fractions. To find a common denominator, you sometimes need to multiply both the numerator and denominator of the fraction you wish to change to make it the correct number. For example, 2/10 + 2/5. You need to multiply the top and the bottom of the second fraction to get the denominator of 2/5 to be 10. Once you've multiplied by the correct number to get the same denominator, you can go ahead and add the fractions. Ex. 2/10 + 2/5 -> 2/10 + (2/5)x2 -> 2/10 + 4/10 = 6/10
Until next time,
~Eric
Thursday, January 15, 2009
Math And Science
Did I ever mention that blogging is really quite fun? Especially, when class FE7B has started new units in both math AND science! Well actually in math, we are almost finished our unit on Ratios and Rates already. Ratio: The comparison of two quantities. Rate: The comparison of two quantities with different units of measurement. Unit Rate: A rate with the second term being only one unit. For example 10km/h. We have been learning how to convert and compare all of these ratios and rates. Here is a problem that class FE7B could encounter in this unit.
Sheila ran 3km in 15 minutes. Stacy ran 4000m in 20 minutes. Stacy said that she ran faster than Sheila did. Is Stacy right?
The first step is to convert these rates into the same unit of measurement. IF we know 1000m = 1 km then we also know that 4000m= 4km.
The second step is to convert both rates into their simplest form. 3 divided by 3 equals 1, so 15 divided by three equals 5. What ever you do to one term, is applied to the other term as well. 4km divided by 4 equals 1 and 20 divided by 4 equals 5.
The rates are both 1km/5 minutes.
So, the answer is: No, Stacy is not right. Both Sheila and Stacy ran the same speed.
For science we have really gotten into the unit on pure substances and mixtures. Not only has class FE7B been learning very valuable note taking skills, but we have been connecting previous knowledge to newly learned information. Here are some key words that we have learned.
Heterogeneous- A mixture with two or more different sets of properties. Homogeneous- A mixture that's parts all have the same composition and properties. Pure Substance- Materials whose properties are not a blend, but are all the same. All of the particles are identical and the properties are effected by particles.
An example of a homogeneous mixture is kool aid mix with water
An example of a heterogeneous mixture is oil and vinegar
An example of a pure substance is gold.
That is basically all of what class FE7B has covered. I'll write next week!
Sheila ran 3km in 15 minutes. Stacy ran 4000m in 20 minutes. Stacy said that she ran faster than Sheila did. Is Stacy right?
The first step is to convert these rates into the same unit of measurement. IF we know 1000m = 1 km then we also know that 4000m= 4km.
The second step is to convert both rates into their simplest form. 3 divided by 3 equals 1, so 15 divided by three equals 5. What ever you do to one term, is applied to the other term as well. 4km divided by 4 equals 1 and 20 divided by 4 equals 5.
The rates are both 1km/5 minutes.
So, the answer is: No, Stacy is not right. Both Sheila and Stacy ran the same speed.
For science we have really gotten into the unit on pure substances and mixtures. Not only has class FE7B been learning very valuable note taking skills, but we have been connecting previous knowledge to newly learned information. Here are some key words that we have learned.
Heterogeneous- A mixture with two or more different sets of properties. Homogeneous- A mixture that's parts all have the same composition and properties. Pure Substance- Materials whose properties are not a blend, but are all the same. All of the particles are identical and the properties are effected by particles.
An example of a homogeneous mixture is kool aid mix with water
An example of a heterogeneous mixture is oil and vinegar
An example of a pure substance is gold.
That is basically all of what class FE7B has covered. I'll write next week!
Wednesday, January 14, 2009
Hi!
In Science we have been learning all about fluid pressure. Next Science class (which I think is tomorrow...) Mr. F will tell us about the summative assignment we are doing for this unit. So far we know that it has something to do with hydraulic systems and building something, so I'm guessing we are building a hydraulic system. Hydraulic systems are systems that use fluids under pressure to create movement. An example of one of these is a barber's chair. The air in the raising/lowering device is under pressure. When you press on the pedal, it opens up a hole at the top of the container the air is in. When a fluid is under pressure, the particles will all rush out quickly and with a lot of force if a hole is opened. So, that is what the air does. That force is applied to the chair, pushing it upwards. That's an example of a hydraulic system. I can't wait for our summative!
In Math have learned how to multiply fractions, and soon we will learn how to divide fractions and how to turn a fraction to a decimal and back again. I will keep you updated.
Until next Wednesday,
-K
In Science we have been learning all about fluid pressure. Next Science class (which I think is tomorrow...) Mr. F will tell us about the summative assignment we are doing for this unit. So far we know that it has something to do with hydraulic systems and building something, so I'm guessing we are building a hydraulic system. Hydraulic systems are systems that use fluids under pressure to create movement. An example of one of these is a barber's chair. The air in the raising/lowering device is under pressure. When you press on the pedal, it opens up a hole at the top of the container the air is in. When a fluid is under pressure, the particles will all rush out quickly and with a lot of force if a hole is opened. So, that is what the air does. That force is applied to the chair, pushing it upwards. That's an example of a hydraulic system. I can't wait for our summative!
In Math have learned how to multiply fractions, and soon we will learn how to divide fractions and how to turn a fraction to a decimal and back again. I will keep you updated.
Until next Wednesday,
-K
Friday, January 9, 2009
A Math-Science Sandwich From FE8A
Mom song
The song above is very funny i think every one would like it.
Science
This week in science we learned about pressure in fluids. One thing that was a large topic during one class was the way in which your ear worked (if you are in grade 8 would would have seen a picture of my face on the smart-board) and what happens when you are sick. Also we talked a lot about the circulatory system which relies on pressure entirely. The reason is when the heart is beating it acts like a pump that draws in blood and after the heart has pumped enough blood the valve shuts and blocks off the blood flow. On the second beat that blood is pushed into the 2 large veins in your body, that branch off in to smaller veins and those veins into smaller ones. A cool fact: it takes 16 minutes for all the blood in your body to circulate your body once.
Math
This year we stared the unit: Fractions and Decimals. this unit so far consists of reducing fractions, adding, subtraction, mixed numbers, improper fractions and we have yet to start the decimals unit.
See you next time.
-Eric
The song above is very funny i think every one would like it.
Science
This week in science we learned about pressure in fluids. One thing that was a large topic during one class was the way in which your ear worked (if you are in grade 8 would would have seen a picture of my face on the smart-board) and what happens when you are sick. Also we talked a lot about the circulatory system which relies on pressure entirely. The reason is when the heart is beating it acts like a pump that draws in blood and after the heart has pumped enough blood the valve shuts and blocks off the blood flow. On the second beat that blood is pushed into the 2 large veins in your body, that branch off in to smaller veins and those veins into smaller ones. A cool fact: it takes 16 minutes for all the blood in your body to circulate your body once.
Math
This year we stared the unit: Fractions and Decimals. this unit so far consists of reducing fractions, adding, subtraction, mixed numbers, improper fractions and we have yet to start the decimals unit.
See you next time.
-Eric
Wednesday, January 7, 2009
My first blog in 2009!
Hey everybody!
Well, there has been only three days so far after the break and, let me tell you, we have already done so much! It's a bit of a contrast to over the holidays where I did next to nothing... But anyways here is what we have been learning in math and science.
We have only had one science class so far, but it was definitely an memorable one. To introduce our new part of the fluids unit, Mr. Foster did an experiment for us. He balanced a meter stick half on a desk and half off of it. On the side that was on the desk, he put three pieces of newspaper. He then said we had to make a prediction to what would happen if he got a metal bar and hit (hard!) down onto the side of the meter stick hanging off the desk. Our choices were:
a) nothing would happen
b) the meter stick would split the newspaper in half
c) the meter stick would break where the paper meets the wood
or d) the paper would be lifted up
I personally chose answer d) because I was thinking of the meter stick like a first class lever, in which case the load (the newspaper) would be lifted. I wasn't counting on Mr. Foster whacking the meter stick as hard as he did; I thought it would be a more smooth, slow movement.
But no, Mr. Foster hit the meter stick like it he wanted to kill it. Everyone in the class was so surprised at the huge "BANG" that was made. I think my heart skipped a beat I was so surprised!
So, what actually happened was c). The meter stick split in half where the paper had been sitting on it. And this was because of pressure (our new sub-unit). There was a ton of air particles in the room exerting a great amount of force on the large surface area of the newspaper so even though Mr. F whacked the meter stick with all his might, it was next to nothing compared to the air particles on the paper. So the force that Mr. F exerted on the meter stick went to where the paper met the wood, breaking it in half.
Overall, it was a very interesting experiment (as petrifying as it was at the time) and we learned a lot from it.
In math we started a new unit on fractions. Right now, our sub unit is on how to add and subtract fractions. We have learned about converting improper fractions to mixed numbers and back again, adding mixed numbers, adding improper fractions, and just adding normal fractions. I can't wait for the rest of the unit!
Until next Wednesday,
-K
Well, there has been only three days so far after the break and, let me tell you, we have already done so much! It's a bit of a contrast to over the holidays where I did next to nothing... But anyways here is what we have been learning in math and science.
We have only had one science class so far, but it was definitely an memorable one. To introduce our new part of the fluids unit, Mr. Foster did an experiment for us. He balanced a meter stick half on a desk and half off of it. On the side that was on the desk, he put three pieces of newspaper. He then said we had to make a prediction to what would happen if he got a metal bar and hit (hard!) down onto the side of the meter stick hanging off the desk. Our choices were:
a) nothing would happen
b) the meter stick would split the newspaper in half
c) the meter stick would break where the paper meets the wood
or d) the paper would be lifted up
I personally chose answer d) because I was thinking of the meter stick like a first class lever, in which case the load (the newspaper) would be lifted. I wasn't counting on Mr. Foster whacking the meter stick as hard as he did; I thought it would be a more smooth, slow movement.
But no, Mr. Foster hit the meter stick like it he wanted to kill it. Everyone in the class was so surprised at the huge "BANG" that was made. I think my heart skipped a beat I was so surprised!
So, what actually happened was c). The meter stick split in half where the paper had been sitting on it. And this was because of pressure (our new sub-unit). There was a ton of air particles in the room exerting a great amount of force on the large surface area of the newspaper so even though Mr. F whacked the meter stick with all his might, it was next to nothing compared to the air particles on the paper. So the force that Mr. F exerted on the meter stick went to where the paper met the wood, breaking it in half.
Overall, it was a very interesting experiment (as petrifying as it was at the time) and we learned a lot from it.
In math we started a new unit on fractions. Right now, our sub unit is on how to add and subtract fractions. We have learned about converting improper fractions to mixed numbers and back again, adding mixed numbers, adding improper fractions, and just adding normal fractions. I can't wait for the rest of the unit!
Until next Wednesday,
-K
Tuesday, January 6, 2009
2009 Blogging
Happy New Year! I hope everybody had a great vacation and are ready to work! Class FE7B has already started new units for both math and science! So far in math, we just recently were told that we will be starting a new unit about Ratios and Rates! A ratio is a comparison of two different numbers and are used in everyday problems and I'm sure this unit will help us all with simple mathematics skills.
Here is a problem that could occur involving ratios.
Francis decided to have a garage sale of all her old toys when she was younger. In total she had 12 dolls, 6 rubber balls, one yo-yo, and 1 set of paintbrushes. By the end of the garage sale Francis had only 3 dolls and 2 rubber balls. Francis wants to know how many items she sold.
We can use ratios to figure this problem out.
Francis had 20 items in total. She sold her yo-yo, her paintbrush set, 6 of her twelve dolls, and 3 of her 6 rubber balls. In total, she only has 9 items left of the 20. We can present this ratio as a part to whole. 9:20. In total, she sold 11 items with 9 items left over. We can present this ratio as a part to part. 9:11.
Ratios are fun and are used everyday! Class FE7B is very excited to see what we will learn in this unit!
As for science, we have only begun our unit on pure substances and mixtures so I will tell you readers next week about what we learned. Here is a safe website on pure mixtures and substances for anyone who wants to learn more about this unit. http://www.chem4kids.com
Have fun and I'll write next week!
Here is a problem that could occur involving ratios.
Francis decided to have a garage sale of all her old toys when she was younger. In total she had 12 dolls, 6 rubber balls, one yo-yo, and 1 set of paintbrushes. By the end of the garage sale Francis had only 3 dolls and 2 rubber balls. Francis wants to know how many items she sold.
We can use ratios to figure this problem out.
Francis had 20 items in total. She sold her yo-yo, her paintbrush set, 6 of her twelve dolls, and 3 of her 6 rubber balls. In total, she only has 9 items left of the 20. We can present this ratio as a part to whole. 9:20. In total, she sold 11 items with 9 items left over. We can present this ratio as a part to part. 9:11.
Ratios are fun and are used everyday! Class FE7B is very excited to see what we will learn in this unit!
As for science, we have only begun our unit on pure substances and mixtures so I will tell you readers next week about what we learned. Here is a safe website on pure mixtures and substances for anyone who wants to learn more about this unit. http://www.chem4kids.com
Have fun and I'll write next week!
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