Uses and examples of Static Electricity

Uses and examples of Static Electricity

1.     Photo Copiers:

All you need to do when working a photocopier is adjust the paper in the allocated scanning area and configure some options and your document or paper is photocopied. So what really happens under that cover? A photo copier actually uses static electricity to move text and pictures from the original document into other paper copies. We know that opposites attract and that if you rub an object such as a rubber balloon with human hair ,negatively charged electrons will start jumping from your hair to the balloon leaving your hair positively charged. If you then bring the balloon close to your hair you will observe static electricity and will find that your positively charged hair is being attracted to the negatively charged balloon. This concept is used in the photocopier where the balloon is a special drum made of photoconductive material that is negatively charged with a corona wire. The copier also contains a very fine black powder known as a toner or black ink and can be attracted by the drum full of a negative form of static electricity. The drum is only selectively charged by the corona wire on the areas of the image where there is black and not charge the drum on the areas that are white. In that way the black ink is only attracted in those areas and an image is created. This concept is also used for colored ink.

Citation:

1.Meeker-O'Connell, Ann.  "How Photocopiers Work."  01 February 2001.  HowStuffWorks.com. 28 May 2010.

2. "Uses of Static Electricity." HubPages. Web. 28 May 2010. .

2.     Car Painting

Weirdly enough, car painting is another real-life example on how static electricity is used. Have you ever wondered how paint will stick to a car? Well, the paint used to paint the car is first charged with a negative static charge using the spray while the metal body of the car is submerged in a substance that will create a positive static charge on it. In that way the paint will be attracted to the car part using through the concept of opposite charges attract. This will ensure two things. First, that now there is a uniform layer of paint so that when there is enough negative paint on the car, the new paint will repel the old paint that was already on the car. Second, this uniform layer is able to resist high speeds and weather conditions to ensure that the car’s metal interior is protected and that the paint won’t come off.

Citation:

1. "WikiAnswers - How Do You Paint Using Static Electricity." WikiAnswers - The Q&A Wiki. Web. 28 May 2010. .

2. "Uses of Static Electricity." HubPages. Web. 28 May 2010. .

3.     Dust Removal

To myself, this is probably the last thing I thought static electricity could be able to do. To my own surprise, static electricity is used to help appliances such as air purifiers and enable dust removal. This occurs by the appliance altering static charges to the dust particles allowing a force to pull the dust particles to a plate or filter in the air purifier that is oppositely charged also using the concept of opposites attract. The same concept is used in industrial smoke stacks where their aim is reduce the percentage of pollution that they are producing as a waste product. Static electricity is used the same way as in the air purifier to enable pollution control. It works by also altering static charges to the dirt and dust particles which then cling on to oppositely charged collecting plates on the upper area inside the smoke stack because of the concept of opposites attract. In this way a reduction to the amount of pollution that is created and that will enter the atmosphere.

Citation:

1."Uses for Static Electricity - Succeed in Understanding Physics: School for Champions." School for Champions: Online Lessons for Those Seeking Success. Web. 28 May 2010. .

2."Uses of Static Electricity." HubPages. Web. 28 May 2010. .

Respiratory System Worksheet

Respiratory System Worksheet


Q2. List the structures in the order in which air passes them as it travels from the nose to the lungs.

1. Pharynx
2. Trachea
3. Bronchi
4. Bronchioles
5. Alveoli

Q3. Which is the odd one out?

Nasal Cavity


Q4. How are dust particles that enter the respiratory system in the air expelled?

Via the nasal cavities where the immune system starts to work o keep out bacteria. Dust particles also sometimes cling on to hairs called cilia.


Q5. Add the correct terms from the list below to the following descriptions


a) Smallest respiratory passageways (Bronchioles)
b)Separates mouth from the nose (Palate)
c)Windpipe (Trachea)
d)where gas exchange takes places (Alveoli)
e)Stops food "going the wrong way" i.e. choking during swallowing (Epiglottis)
f) Both air and food pass through this (Pharynx)
g) The movement of air out of the lungs (Expiration)
h) The main muscle involved in inspiration (Diaphragm)
i) Membranes that cover the lungs and line the pleural cavity (Pleura)
j) The volume of air inhaled or exhaled at each normal breath (Tidal Volume)





Q6. Arrange these statements in the right order to describe inspiration.



The muscles between the ribs contract to move ribs cranially and laterally. The diaphragm contracts and flattens. The lungs expand to fill the space created. The air pressure in the air tight pleural cavities decreases. Air is drawn down the trachea into the lungs.




Q7. True or false? Circle the correct answer

a) The pericardium is the membrane surrounding the lungs.(True)
b) The tidal volume describes the maximum amount of air that can be inhaled into the lungs (False, it is inhaled and expired)
c) The epiglottis closes off the larynx during swallowing (False)
d)When an animal exercises the rate of breathing increases because the carbon dioxide in the blood increases.(True)
e)Carbon Dioxide in the blood is mainly carried in the blood plasma (True)
f)Oxygen moves from the alveoli into the capillaries by the process of osmosis(False, The gas diffuses)
g)Expired air contains about 16% of oxygen.(True)



Q8. Add the following labels to the diagram of a section cut across lung alveoli shown below.











 

Asthma and Smoking Brainpop Videos

Asthma and Smoking Brainpop Videos

• Asthma:

Asthma is a condition that occurs to the lungs and is very common. People with asthma experience frequent coughing, shortness of breath and tightness in the lungs followed by several asthma attacks. When our lungs inhale oxygen or in other words when we breath millions of small air sacks called alveoli oxygen starts to enter the blood while carbon dioxide is expelled out of our bodies. An asthma attack is usually triggered when dust particles, pollution, mold, etc enter the body of someone with the asthma condition. They enter the lung air ways which causes a chemical called mucus to be released causing swelling and makes the airways narrow making it almost impossible to breath. Other factors such as food allergies, exercise, weather and sometimes strong emotions. With proper doctor's care, a person with asthma conditions can do sports and other activities with the help of his/her asthma inhaler which launches medicine that will reduce the swelling and expand the lung airways making breathing easier again.

• Smoking:

Smoking is one of man's worst bad habits. It is basically a drug that is made out of tobacco as well as many other chemicals such as tar and the very addictive, nicotine. Our lungs have a job to do, they are made to inhale oxygen and distribute it among the rest of the body then exhale the waste product which is carbon dioxide. Inhaling, smoke instead of oxygen causes the lungs to literally start getting coated with tar causing damage to it cells and also causing it start changing in color to black. This affects the human being over time and causes diseases such as emphysema, lung cancer and heart disease. Other than diseases, smoking also has some other side effects, including developing shortness of breath and constant coughing which are caused by the lungs having too much tar that makes it harder to inhale oxygen and transfer it to the rest of the body. Finally, smoking can be really hard to quit, as you can see, many smokers will have trouble leaving this very bad habit because of the excess nicotine that supposedly gives the smoker 'pleasure' while smoking.

Healthy and Unhealthy Foods

Healthy and Unhealthy Foods

Unhealthy foods contain different things that can harm the human body and can cause different diseases overtime. Excess calories is one of the greatest contributers in becoming fat and increase Unhealthy foods especially fast food such as McDonald's contain a lot of excess calories leading to becoming fat or other overweight diseases such as Diabetes and high blood pressure e.g. 1 Big Mac meal= 2000 calories which is more than 60% of the calories needed per day. Saturated fats is another factor that causes diseases and is in most fast food. More saturated fats will cause plaque to start to build up in your arteries and could cause blood to stop going through to certain parts in the body. Unhealthy food usually contains high amounts of salt which assumably tastes good for most human beings. High sugar is basically the same and is in sodas, chocolates and other unhealthy foods. High salt could cause high blood pressure while high sugar could cause more amounts of insulin made by the pancreas causing the blood sugar to go high then low. Empty calories are another element in unhealthy foods and contain little minerals and little vitamins but are found a lot in unhealthy food. Therefore, they cause the human being to keep eating but not benefit from the food and ends up with less vitamins and/or minerals but also keeps the human being eating since he/she are not full yet. This is oppisite to healthy food which makes you full really quickly without the need to eat too much. Healthy also contains low calorie and saturated fats as well as high fiber which can't be digested. All these build up the human body in the correct way with less fats and more protien and minerals keeping the healthy brain in the helathy body.

Parts of the Digestive System

Parts of the Digestive System

In this unit, we covered the digestive systems and wrote some notes on all the parts of the digestive system on our laptops. Since my laptop was in IT Support, I figured that if I write my notes on paper, I could later on take clear photographs of the notes and successfully have a paper and digital copy of my notes. Here are the photos that show the notes that cover the digestive system:

What is my MYP grade?

What is my MYP grade?

Abdelrahman has been really keeping a consistent effort throughout the year and has been showing outstanding results in each of his criteria. His high scores led to an overall academic grade of 7. Although Abdelrahman showed a great academic performance, he slightly lacks the ability to focus on his studies at all times and sometimes shows less effort in class. Abdelrahman can improve by trying harder to get homework assignments done on time as well as focusing in class and getting all his agendas down. This will help Abdelrahman continue his success and his academic performance as well as showing 100% effort at all times by completing the assigned homework on his blog and writing the agenda down preferably on his digital notebook that was supposed to be downloaded.

The Mouth

The Mouth

In this part of the digestive system, food is physically broken down into small bits. Saliva

slimes the food so that it can easily slide down the Esophagus and carbohydrates are started to

be broken down chemically.

Speed, Velocity and Acceleration Relationships

March 10th 2010

• What is Speed?

Speed is basically the measurement of an object's motion whether it is accelerating or decelerating and is usually measured in m/s. Speed is found when dividing the covered distance and the amount of time taken to cover it. E.G. The athlete sprinted the 100m race and finished in 10 sec, therefore his speed is:

100 m ÷ 10 sec

= 10m/s

• What is Acceleration and Deceleration?

Acceleration is when an object is starts to speed up. E.g. A skydiver falling would accelerate or generate speed as he/she is falling. Deceleration however, is when an object slows down. E.G. If a skydiver deploys his/her parachute, it will create air resistance causing him/her to slow down or decelerate.

• What is Velocity?

Velocity however, is also the measurement of an object's motion as well as its direction and displacement. Velocity tells us the speed of the object as the direction in which it is going E.G. If a car moves in reverse and covers 70 m in 1 second, the average speed would be 70m/s while the average velocity would be - 70m/s. This is because the car is going in the oppisite direction and therefore has a negative velocity. The speed remains the same since speed is only the measure of how fast or slow an object's motion is and disregards direction.

• What is Terminal Velocity?

Terminal Velocity is basically when an object reaches at a stable and balanced velocity. Take a skydiver for example, he/she will continue accelerating due to the force of gravity that is acting on him/her. The acceleration will come to an end after air resistance starts to increase and balances out the gravitational forces. When that balance had been made then the person would have reached terminal velocity.

• Is there any difference between Speed and Velocity?

Of course there is, but it is not clear or visible. Speed is measuring only how fast or slow an object's motion is, while velocity measures that and the direction of that motion. Look and compare these two graphs:

Graph A:

Graph B:

These two graphs are both a speed graph and a velocity graph respectively. As you can see the difference between these graphs is that one graph measures just the speed of the object and the other measures the speed and direction. One evidence is that in the velocity graph, the velocity goes under zero. This means that the object is going in the opposite direction.

The Speed and Weight on Moon

March 7th 2010

How did I calculate my walking and running speed?

I calculated my walking and running speeds similarly. First, I set up 2 cones at a distance of 10m from each other. Next, I walked the distance while being timed and did the same for running. My running and walking times were then put on the Distance, Speed and Time triangle:

• Walking:

Speed

= Distance÷Time

= 10 m ÷ 5.5 sec

= 1.8 m/s

• Distance:

Speed

= Distance÷Time

= 10 m ÷ 2.47 sec

= 4.1 m/s

Why are our weights different on other planets?

This is because your weight depends on the mass of the planet, the distance you are from the center of the planet and the amount of force that is applied on you while you are on the planet. E.g. On earth, you are applied with 10N of force while on the moon you are only applied with 1.6N of force, therefore your weight decreases while on the moon.

Newton's 3 Laws of Motion

• First Law: The law States that an object in motion will stay in motion as long as there is no unbalanced force acting on it. If a force acts on the object, the object will change speed or direction.

E.G. When a car with luggage that is not properly tied on its top has to suddenly stop, only the car will stop but the rope doesn't provide enough force to stop the luggage from moving therefore causing it to continue moving seeing that there is no unbalanced force acting on it. We humans however are stopped by the seatbelt which provides enough force to stop us from moving.

• Second Law: The law States that if an unbalanced force is acting on an object it will cause it to accelerate in the direction of that force.

E.G. If a person on roller skates is pushed by another person, the person on roller skates will start accelerate in the direction that his partner pushed him to( applied unbalanced force).

• Third Law: Forces always occur in equal or opposite pairs. A moving object will apply force to a stationery object and will cause itself to move corresponding to the amount of force applied.

E.G. If a person is sitting on a wheeled chair(moving object) and pushes his desk(stationery object), he would receive the same amount of force from his desk causing him to move corresponding to the amount of force he had applied.

Mechanical Advantage Worksheet

25th February 2010

Questions:

Answers:

Work and Machines Questions

Tuesday February 16th 2010

Pg 80

Questions:

1. What is meant by:

a)doing work

b)a machine

2. Are you doing work when you are:

a)pushing the mower

b)cleaning your teeth

c)cycling

d)reading this page

Explain your Answers

3. Why must you eat if you are going to keep working?

4. Why are spanners, pliers and can openers called machines?

5.Try to find out the names of other simple machines.

Answers

1.

a)Using a force to move an object

b) anything that makes work easier

2.

a)Yes,because you are applying a force to the mower making it move or change direction.

b)Yes, because you are applying force to the toothbrush thus,moving it and brushing your teeth.

c)Yes, because you're your applying force with your legs to the pedals top move the bike forward and applying force with your arms to the handle bar to steer.

d)No, because your are not applying an force

3.Energy is related to work and is needed when doing work. Food provides energy so work is interdependent upon food and energy to occur.

4.This is because they are a way to make work easier thus being machines.

5.Examples of Simple Machines:

• Incline Plane
• Levers
• Wheel and Axle
• Screw/Nail

Pg 81

Questions

1. What do you need to make a pulley system?

2. Give two reasons why it is easier for a mechanic to lift a car engine out using a pulley system?

3. What is the job of:

a)the chain

b)the gears on a bicycle

4.Turning a bicycle crankshaft turns the back wheel.What is the difference between cycling high gear and low gear?

Answers

1.You need a set of pulley wheels and a rope

2. Two Reasons:

• A pulley is a machine that makes work easier thus making it thus making it easier to lift the engine off the ground.
• Since there is more distance, less force is required to lift the engine off.

3.

a)

• The chain transmits the force applied to the pedals to the back of the wheel, turning them.
• The gears of a bicycle change the number of times that one turn of the crankshaft turns the back wheels.

4. At a high gear, the chain runs over the small cog wheel at the back so that one turn of the crank turns the back wheel several times and is used on flat surfaces. A low gear however is used for climbing steep surfaces and the chain runs on a larger cog wheel therfore turning the back wheel only once or twice.

Pg 82

Questions

1. Which simple machines were used:

a) to split the blocks

b) to move the blocks

c) to put the blocks in place

2.

a)How has friction reduced when the block were moved?

b)A simple invention, first used 700 years after the Pyramid was built, would have reduced friction further. What is it?

3. Draw a diagram to show how to lift a block of stone using a lever.

4.Wedge shaped tools and ramps are still in use. Give some examples of how they are used.

5.How much work had to be done to raise the last block(weighing 25,000 N) on to the top of the pyramid?

Answers:

1.

a)Wedges

b)Huge Ramps

c)Ramps and Rollers

2.

a) By using rollers, the Egyptians were able to reduce the amount of friction. This is because rollers are circular and round and are able to roll on the ground easily, while the blocks were squared and therefore produced a lot of friction when moved on the ground.

b) The Wheel and Axle

3.

4. Wedges are used for lifting and separating E.G. Forks are considered wedges since they split and separate the material ( Food) when used. Other uses for the wedge is for holding fast E.G. A Wedge-type door stopper uses friction to stop a door from moving as well as using it to create a firm grip to the floor.

5. Since the distance is 140m and the amount force needed is 25,000N, therefore:

Work

= Force x Distance

= 25000 x 140

= 3,500,000 Joules

What are Machines ?

Monday February 15th 2010

Forces Questions

Questions:

1. What is a Force?
2. Give 4 Examples of Forces
3. Units of Forces?
4. Equation of a Force?

Answers:

1. A force is basically a push or pull on an object that can either change its direction, speed or shape.
2. Here are a few examples of forces:
   • Friction is an example of a force and happens 2 surfaces are rubbed together causing the object to slow down and producing heat e.g. a car moving on the street creating friction between the tires and the street.
   • Air Resistance is a force that happens between a moving object and air pushing it in a speed and direction dependent on the wind direction and speed e.g. A fast cyclist cycling against the wind.
   • Gravity is a very common example of a force and is an attractive force between objects and the earth and causes an object to be pushed down on the earth depending on its mass; the bigger the object, more the mass of the object and the more the gravity e.g. an apple falling from a tree to the ground.
   • A magnetic field is a force that occurs between a two magnets or a magnet and a magnetic metal (Iron), it causes the magnets to either attract or repel depending on how the magnet's domains are lined up e.g. two magnets beside each other with the same south pole; they will repel.
3. Forces are measured in Newtons
4. Forces Equation:

F=Mass x Acceleration

E.G.

F= 50 KG x 10m/s^2

=9.8 m/s^2

Food Web in the Sage Brush-Steppe Ecosystem

January 18th 2010

1.a) Insects,Squirrels and other small rodents and Pronghorn and other grazers.

b) Raptors and Badgers

c) Bats, lizards and small reptiles

d) No organism eats mountain lions

2. Killing coyotes for absolutely no reason with no organism to feed on it might cause various factors to the organisms in this food web. First, the coyote population would decrease leaving no or less predators for the prey, the pronghorn and other grazers. This could cause an increase on their population leading to more plants being consumed and decreasing the amount of plants thus leaving less food for herbivores such as squirrels, insects or even humans causing a decrease to most of their populations.

3. This increase of the mountain lion population could cause its prey, prong horn and other grazers to decrease, leaving coyotes with half the supply of food they already had allowing its prey to reproduce and increase in population. Other effects such as the decrease of pronghorns and other grazers could cause plants to increase leaving the other primary consumers, insects squirrels and other small rodents, with more food, increasing their population. This will give the predators of these organisms more prey to feed on and also increasing their population. So, this all moves in a big cycle and all animals are interdependent upon each other balancing out this food web.

4. Mesquite trees require a great deal of water leaving other plants with no water to germinate. This could cause a great decrease in other plants causing primary consumers to decrease which will eventually affect all organisms in the ecosystem. Many animals feed on seed pods produced by the mesquite trees, this could balance out the food web and giving primary consumers food to feed on and continuing the food web as it was at first.

Science H/W

Science H/W

In this blog I will basically be posting the H/W we are usually assigned and they will just appear in order of date(The Newer H/W at the top and the older at the bottom). I have tried to make it as easy as possible to access this blog and I hope you have no trouble viewing my H/W assignments at all.