The pennies before the vinegar/salt bath:
And these are the pennies after:
Thursday 12 January 2012
Lab Pictures
For the portfolio, I had to do a lab, and that's in the binder I'm handing in. But I wanted to put in some pictures I took of the pennies. So here they are:
The pennies before the vinegar/salt bath:
And these are the pennies after:
The pennies before the vinegar/salt bath:
And these are the pennies after:
Monday 2 January 2012
Physics #2
For this post, I'm going to post questions from the textbook
Page 376
Question 12: The traffic sign at the beginning of a school zone reads "30 km/h" Is this sign a 'speed zone' sign or a 'velocity zone' sign? explain your answer.
Answer: To me, the sign in a 'speed zone' sign. This is because the sign only tell the speed, and not the direction the car needs to go.
Question 16: The SI unit for average speed or average velocity is m/s. What is another common unit used for these two concepts?
Answer: Another common unit is km/h
Page 377
Question 20: A girl rides her bike 420m south in time of 47s. What is her average velocity?
Answer: V=d/t, V=420/47, V=9m/s
Page 391
Question 8: A) If the acceleration is in the same direction as the velocity, what happens to the speed of an object
Answer: The speed of the object will increase
B) If the acceleration is in the opposite direction to the velocity, what happens to the speed of an object?
Answer: The speed of an object will decrease.
Question 9: A car traveling forward at 25m/s stops and backs up at 4m/s
A) What is the car's change in velocity?
Answer: The change in velocity is 21m/s
B) What is the direction of the car's acceleration?
Answer: Backward
Page 397
Question 1: A car starting from rest accelerates uniformly to 15m/s [E] in 5s. What is the car's acceleration?
Answer: A=^V/t, A=15m/s / 5s, A=3m/s2 [E]
Page 405
Question 2: What does the slope of a velocity-time graph represent?
Answer: The slope represents the acceleration of an object.
Question 6: In the absence of air resistance, what is the magnitude and direction of the acceleration due to gravity near the surface of Earth?
Answer: The acceleration due to gravity is 9.8m/s2 downward.
Question 8: What is the acceleration of a golf ball that is accelerated uniforly from rest 55m/s forward in 0.00045s?
Answer: A=^V/t, A=55/0.00045, A=12222.23m/s2
I thought these questions were important to the unit because it shows air resistance, gravity, the slope, and equations. If I didn't know how to factor in all of these, and to do the equations, I wouldn't have been able to pass the unit, or understand what my teacher was talking about, and luckily I did.
Page 376
Question 12: The traffic sign at the beginning of a school zone reads "30 km/h" Is this sign a 'speed zone' sign or a 'velocity zone' sign? explain your answer.
Answer: To me, the sign in a 'speed zone' sign. This is because the sign only tell the speed, and not the direction the car needs to go.
Question 16: The SI unit for average speed or average velocity is m/s. What is another common unit used for these two concepts?
Answer: Another common unit is km/h
Page 377
Question 20: A girl rides her bike 420m south in time of 47s. What is her average velocity?
Answer: V=d/t, V=420/47, V=9m/s
Page 391
Question 8: A) If the acceleration is in the same direction as the velocity, what happens to the speed of an object
Answer: The speed of the object will increase
B) If the acceleration is in the opposite direction to the velocity, what happens to the speed of an object?
Answer: The speed of an object will decrease.
Question 9: A car traveling forward at 25m/s stops and backs up at 4m/s
A) What is the car's change in velocity?
Answer: The change in velocity is 21m/s
B) What is the direction of the car's acceleration?
Answer: Backward
Page 397
Question 1: A car starting from rest accelerates uniformly to 15m/s [E] in 5s. What is the car's acceleration?
Answer: A=^V/t, A=15m/s / 5s, A=3m/s2 [E]
Page 405
Question 2: What does the slope of a velocity-time graph represent?
Answer: The slope represents the acceleration of an object.
Question 6: In the absence of air resistance, what is the magnitude and direction of the acceleration due to gravity near the surface of Earth?
Answer: The acceleration due to gravity is 9.8m/s2 downward.
Question 8: What is the acceleration of a golf ball that is accelerated uniforly from rest 55m/s forward in 0.00045s?
Answer: A=^V/t, A=55/0.00045, A=12222.23m/s2
I thought these questions were important to the unit because it shows air resistance, gravity, the slope, and equations. If I didn't know how to factor in all of these, and to do the equations, I wouldn't have been able to pass the unit, or understand what my teacher was talking about, and luckily I did.
Info
Ok, so as I'm not going to be able to post some of the stuff that I have to have in the portfolio, such as the lab and the title page, I'm going to hand those in in a booklet. Just letting you people know :)
Sunday 1 January 2012
Physics #1
For the first post on the physics unit, I'm going to write down all of the key words for chapter 8 and chapter 9
Acceleration: the rate at which an object changes it's velocity
Acceleration Due To Gravity:...in the absence of gravity; the value of acceleration due to gravity near the surface of the Earth is approximately 9.8 m/s2 downward
Air Resistance: a friction-like force that opposes the motion of objects that move through the air.
Average Acceleration: average rate at which an object changes it's veloctiy shown by the slope of a velocity-time graph.
Average Velocity: the rate of change in position for a time interval.
Change In Velocity: change the occurs when the speed, the direction, or both of an object calculated by subtracting the initial velocity from the final velocity.
Constant Acceleration: velocity changing at a constant rate
Deceleration: acceleration that is opposite to the direction of motion; a decrease in speed.
Displacement: the straight line distance and direction from one point to another.
Distance: a scalar quantity that describes the length of a path between two points or location.
Gravity: attractive force between two or more masses
Position: a vector quantity that describes a specific point relative to a reference point.
Position-time graph: a graph of an objects position during corresponding time intervals.
Scalars: quantities that only have magnitude.
Slope: the direction of a line on a graph.
Uniform Motion: traveling in equal displacement in equal time intervals.
Vectors: quantities that have both magnitude and direction
Velocity: the displacement of an object during a time interval divided by the time interval
If I didn't know what these words meant, I wouldn't have been able to understand the unit...at all. But I do, so I did.
Acceleration: the rate at which an object changes it's velocity
Acceleration Due To Gravity:...in the absence of gravity; the value of acceleration due to gravity near the surface of the Earth is approximately 9.8 m/s2 downward
Air Resistance: a friction-like force that opposes the motion of objects that move through the air.
Average Acceleration: average rate at which an object changes it's veloctiy shown by the slope of a velocity-time graph.
Average Velocity: the rate of change in position for a time interval.
Change In Velocity: change the occurs when the speed, the direction, or both of an object calculated by subtracting the initial velocity from the final velocity.
Constant Acceleration: velocity changing at a constant rate
Deceleration: acceleration that is opposite to the direction of motion; a decrease in speed.
Displacement: the straight line distance and direction from one point to another.
Distance: a scalar quantity that describes the length of a path between two points or location.
Gravity: attractive force between two or more masses
Position: a vector quantity that describes a specific point relative to a reference point.
Position-time graph: a graph of an objects position during corresponding time intervals.
Scalars: quantities that only have magnitude.
Slope: the direction of a line on a graph.
Uniform Motion: traveling in equal displacement in equal time intervals.
Vectors: quantities that have both magnitude and direction
Velocity: the displacement of an object during a time interval divided by the time interval
If I didn't know what these words meant, I wouldn't have been able to understand the unit...at all. But I do, so I did.
Sunday 27 November 2011
Biology #3
For the last part of the biology unit, I'm putting in questions from the unit review.
3. a) this biome has a permafrost, a short growing season, and no trees: tundra
f) the main vegetation in the biome is coniferous trees: boreal forest
7. Identify each of the following biotic interactions
a) An ant species feeds on the sweet tasting chemicals produced by a caterpillar species. The ants vigorously protect the caterpillars and carry them to their nests at night for safety. This is an example of mutualism.
c) A whip worm lives in the large intestine of a dog and causes the dog to lose mass. This is an example of parasitism
d) A salamander uses it's sticky tongue to capture an insect. This is an example of predation.
9. Using an example of each, compare and contrast the diets of detrivores omnivores, and herbivores.
Detrivores, such as worms, only eat dead organic matter eating at every trophic level. Omnivores, such as bears, eat both plants and meat. Herbivores, such as deer, only eat plants.
14. How do persistent organic pollutants such as DDT affect organisms?
Persistent organic pollutants (POPs) have a long half-life and bioaccumulate in plants, then in fatty tissues of animals. They can also wash into streams and lakes, affecting the aquatic food chain. DDT can cause nervous system, immune system, and reproductive disorders.
16. Describe the harmful effects on humans of bioaccumulations of the following:
a) Lead: lead can cause anemia, nervous system damage, low fertility rates, impaired mental development, and kidney failure.
b) Cadmium: cadmium can cause infertility and damage to the central nervous system, immune system, and DNA
c) Mercury: mercury can cause damage to the nerve cells, the heart, the kidneys, the lungs, and suppresses the immune system.
18. List two abiotic factor the influence ecological succession.
Soil, and water
19. Explain how primary succession differs from secondary succession.
Primary succession occurs on an area where no living things are, where there's bare rock. Secondary succession occurs where there once was living things.
These questions show my understanding from all three chapters of the biology unit.
3. a) this biome has a permafrost, a short growing season, and no trees: tundra
f) the main vegetation in the biome is coniferous trees: boreal forest
7. Identify each of the following biotic interactions
a) An ant species feeds on the sweet tasting chemicals produced by a caterpillar species. The ants vigorously protect the caterpillars and carry them to their nests at night for safety. This is an example of mutualism.
c) A whip worm lives in the large intestine of a dog and causes the dog to lose mass. This is an example of parasitism
d) A salamander uses it's sticky tongue to capture an insect. This is an example of predation.
9. Using an example of each, compare and contrast the diets of detrivores omnivores, and herbivores.
Detrivores, such as worms, only eat dead organic matter eating at every trophic level. Omnivores, such as bears, eat both plants and meat. Herbivores, such as deer, only eat plants.
14. How do persistent organic pollutants such as DDT affect organisms?
Persistent organic pollutants (POPs) have a long half-life and bioaccumulate in plants, then in fatty tissues of animals. They can also wash into streams and lakes, affecting the aquatic food chain. DDT can cause nervous system, immune system, and reproductive disorders.
16. Describe the harmful effects on humans of bioaccumulations of the following:
a) Lead: lead can cause anemia, nervous system damage, low fertility rates, impaired mental development, and kidney failure.
b) Cadmium: cadmium can cause infertility and damage to the central nervous system, immune system, and DNA
c) Mercury: mercury can cause damage to the nerve cells, the heart, the kidneys, the lungs, and suppresses the immune system.
18. List two abiotic factor the influence ecological succession.
Soil, and water
19. Explain how primary succession differs from secondary succession.
Primary succession occurs on an area where no living things are, where there's bare rock. Secondary succession occurs where there once was living things.
These questions show my understanding from all three chapters of the biology unit.
Biology #2
PCBs and the Orcas
From the 1930s to the 1970s PCBs or polychlorinated biphenyls were used in industrial products. In 1977 they were banned in North America as concerns about what the PCBs were doing to the environment were growing. But synthetic chemicals, such as PCBs, bioaccumulate, biomagnify, and have a long half-life. PCBs stay in organisms, suppress the immune system, and may cause cancer in humans. But aquatic ecosystems have taken a hard hit with the PCBs
The animal that was hit the hardest was the orcas. A study found that PCBs will interfere with the orcas reproductive system until at least 2030. Though the chemicals have been banned for decades, the orcas retain high levels of PCBs, especially the calves. The figure shows how biomagnification occurs in orcas. PCBs enter the food chain at a low level in the microscopic plants and algae, but by the time the PCBs reach the orca, they are highly concentrated in the blubber. When the salmon population gets low, magnification is increased, since blubber is burned for energy. The PCBs are then released into the bloodstream where they interfere with the immune function, making the orca more susceptible to disease.
Not only does this show my knowledge of half-lives, which relates back to the chemistry unit, it also shows how pollutants climb up the food chain, as well as bioaccumulation and biomagnification.
From the 1930s to the 1970s PCBs or polychlorinated biphenyls were used in industrial products. In 1977 they were banned in North America as concerns about what the PCBs were doing to the environment were growing. But synthetic chemicals, such as PCBs, bioaccumulate, biomagnify, and have a long half-life. PCBs stay in organisms, suppress the immune system, and may cause cancer in humans. But aquatic ecosystems have taken a hard hit with the PCBs
The animal that was hit the hardest was the orcas. A study found that PCBs will interfere with the orcas reproductive system until at least 2030. Though the chemicals have been banned for decades, the orcas retain high levels of PCBs, especially the calves. The figure shows how biomagnification occurs in orcas. PCBs enter the food chain at a low level in the microscopic plants and algae, but by the time the PCBs reach the orca, they are highly concentrated in the blubber. When the salmon population gets low, magnification is increased, since blubber is burned for energy. The PCBs are then released into the bloodstream where they interfere with the immune function, making the orca more susceptible to disease.Not only does this show my knowledge of half-lives, which relates back to the chemistry unit, it also shows how pollutants climb up the food chain, as well as bioaccumulation and biomagnification.
Biology #1
This is a picture of the nitrogen cycle. Nitrogen is an important component of DNA and proteins. It is also essential for muscle function and growth.
This shows the many different stages of the nitrogen cycle, including nitrogen fixation, nitrification, uptake, and denitrification. The picture also shows where nitrogen is stored, the atmosphere, as well as the different ions that nitrogen is changed into.
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