# Physics coursework – marked A* (60/64marks)

8 August 2016

When an object falls, many forces are acted upon it: gravity, friction, air resistance and, if in the water, up thrust. When an object starts to fall, gravity over powers air resistance, however, as an object starts to reach terminal velocity (its maximum speed) the opposite forces start to even out until they are equal. Some people believe that if the forces are balanced then the object has stopped moving, meanwhile they could also just be moving at a constant speed (its terminal velocity). All free-falling objects accelerate at the same speed no matter what their mass is (9. 8m/s? ).

There are two calculations you need for this investigation, no matter which factor you investigate and they are the equations to work out speed and acceleration. Speed = Distance Travelled Time Taken Acceleration = Change in Velocity Time Taken Many people believe that speed and velocity is exactly the same thing but they are wrong; speed is just a number, but velocity has direction too. Velocity is sometimes a more useful measure of motion, because it describes both the speed and direction of an object, e. g. velocity = 30m/s due north. Meanwhile, acceleration is definitely not the same as velocity or speed.

## Physics coursework – marked A* (60/64marks) Essay Example

Acceleration is the change in velocity in a certain amount of time. The factors affecting the terminal velocity of a falling object include: its mass, its surface area, the viscosity of a liquid and the height of where the object is dropped. In his First Law, Newton explained the effect of a net force, greater than zero, upon an object at rest. In his Second Law, Newton explains the effect of a force upon a moving object and the relationship between acceleration, force, and the mass of an object Isaac Newton’s Second Law of Motion (F=ma) explains the relationship between force and acceleration in motion.

The application of force on an object causes an acceleration of that object. Yet, force is not the only factor in the movement, or acceleration of an object. The two main influences on the acceleration of an object are net force and mass. For example, net force is directly proportional to acceleration while mass is inversely proportional to acceleration. In other words, net force- the force that has overcome friction and accelerates an object- is directly linked to acceleration; the more force you have, the faster an object goes.

Other factors such as the friction, air or fluid resistance, and pressure effect the acceleration as well. All of these factors do not work against or in accordance with acceleration in the same way. [1] One factor that can affect the motion of a falling object is its mass. Mass is a measure of how much stuff is in an object. [2] If the mass is greater, the object will fall fast because there is a stronger gravitational pull on the object, meaning that it will hit the ground quicker than an object with a smaller mass.

However, this is only true for objects falling in a space with air. When you neglect air resistance, all objects fall at the same rate. Feather, bowling ball, dead body — all fall at the same rate. However, in the real world, you generally don’t get to neglect air resistance unless you’re in space or your falling object is dense and doesn’t fall far. In the real world, as things fall they accelerate, first at 9. 8 m/s? but as they speed up the rate of acceleration slows and it’s finally zero at terminal velocity. What really matters is the ratio of air resistance to weight/mass.

If you reduce the weight of something, but its size and shape remain the same, and then it will fall slower than before. If you increase its weight but its shape and size remain the same (i. e. its density increases), then it will fall faster. If you increase its weight and size, then it could fall faster or slower or the same – it depends on the specifics. But in general, if the density remains the same (i. e. it’s made of the same stuff), and the shape remains the same, the larger (and heavier) it is, the faster it will fall.

This is because the weight increases as the cube of the size of an object, but the air resistance (drag) only increases as the square of the size, so the bigger the object is, the faster it will fall (or to be more precise, it has a higher terminal velocity. ) The surface area can affect the motion of the falling object because it is has more air resistance pushing against it. Because there is more air resistance pushing against a larger object, it will fall so because it is making the downward force (gravity) weaker since there is now a larger force counteracting that first force.

An object with a larger surface area will fall slower (have a smaller velocity) because it means there is a large area for air to come into contact with to produce that counteracting force called air resistance. Another factor that can affect the motion of a falling object is the viscosity of the liquid that it is falling through. Viscosity of liquid means how thick the liquid is. The higher the viscosity of the liquid, the more the liquid resists the object which is falling through it. This means that it will take a longer amount of time for the object to fall; meaning the velocity of the object will be very small.

A further factor that can affect the motion of a falling object is the height from which the object is dropped from. Obviously, if an object is dropped from a greater height, it will take longer to reach the ground than the same object to reach the ground if it is a few centimetres away from it. This graph shows how as the height of where the object is drop from decreases, the time taken for the object to hit the ground decreases as well. There are more factors that can affect the motion of a falling object; however these four that I have included in my scientific knowledge are the four main ones.

Preliminary Tests Preliminary experiments are used to ascertain what materials used and why, what ranges we will have and why, and what variables there are and how they can be controlled. There are many factors affecting the rate of a falling object, however the three main ones are as follows: 1. Weight of the object (mass or gravity). 2. Surface area of the object or its’ parachute surface area. 3. Viscosity of the material it is falling through. There are two methods that are available to us at school: the Parachute method, and the Ball Bearing method.

The Parachute method involves dropping an object with a parachute attached to it and timing how long it takes to hit the ground; while the Ball Bearing method involves dropping a metal ball into a measuring cylinder full of glycerol and timing how long it takes to reach a certain point. I am going to use the Parachute method because it is a quicker method and the science department at our school have an endless list of the supplies needed for it. Meanwhile, I am not using the Ball Bearing method because we as a school have a very limited supply of glycerol and we cannot remove the ball bearing very easily afterwards.

There are two variables (factors) we are able to investigate, and they are mass and surface area. For mass I would be dropping the same size parachute every time, however I would be increasing/decreasing the mass on the end of the parachute- for me this would be by adding blue tack to the ping pong ball which is attached to the end of the parachute by string. On the other hand, for surface area I would be keeping the mass of the object the same every time, but I would be increasing/decreasing the size of the parachute I am using – for me this would be by cutting the parachute down by so many centimetres after one set of tests.

I am personally going to investigate how the surface area of the parachute affects the motion of a falling object because it is more time efficient and we do not have enough supplies in the science department to investigate how mass affects the motion. Time or average velocity? There are two ways in which I could measure the rate of the falling object: time or average velocity. I am going to measure the rate of the falling object in velocity so that I can get a more accurate measurement for the motion of the falling object. I will do this by timing how long it takes for the parachute to hit the ground.

Then divide the height from which I dropped it from by the time it took to reach the ground (Velocity = Distance ? Time). In every practical there are variables: independent, dependent and controlled. My independent variable is the concentration of the alkali I use, because the independent variable is the one that you will alter throughout my experiment. [4] Meanwhile, my dependent variable is the difference in temperature after the alkali has been added to the acid, so that we can find out how much energy has been released, because the dependent variable is the variable that you measure.

[5] The controlled variables are the ones that you try to keep constant throughout your experiment so that they don’t affect your experiment to insure that all of the texts have an equal chance of working properly and all the tests have been done fairly. [6] Control How Will I Keep it the Same? Why am I Keeping it the Same? The height from where I drop the parachute. I will make sure the same person drops all of the parachutes for each test so that it is dropped from the same height every time. Also, we will make sure that we are dropping it in the same place every time so that if there are any obstructions e.

g. chairs/doors/tables, they will be there for every test so it is fair. I am keeping this the same because if any parachutes are dropped from a higher/lower point than the rest, the tests will not be very reliable since we would be changing more than just the surface area. The mass of the object attached to the parachute. I will keep this the same by using the same ping pong ball every time by just removing the strings from the parachute and attaching it to the next. That way there will be the same amount of string and sticky tape on it as well.

I am keeping this the same because if any parachutes have a greater/smaller mass than the rest, the tests will not be reliable since we would be changing more than just the surface area. The material used for the parachute. I will keep this the same by starting with the biggest sized parachute and then cut that parachute down to the next size, instead of using another bag. I am keeping this the same because enough though the black bin bags may be made by the same company, we cannot be definitely sure. Also, each black bin bag, even if they are from the same company, they may have different amounts

of polymers in the bags meaning one may be stronger than the other. Before I complete my real tests for my investigation, I had to do some preliminary tests to determine what range of surface areas to use, whether to have support/structure in my parachutes, what height to drop the parachutes from, and where I should drop the parachutes from. The first test I did was to determine what range of surface areas I should use, and these were the results from the tests: Surface Area Time taken to reach the ground (Seconds) Test 1 Test 2 Test 3 Average 400cm2 (20cm by 20cm) 1. 45 1. 25 1. 13 1. 276 900cm2 (30 cm by 30cm)

1. 90 2. 00 1. 81 1. 905 3600cm2 (60cm by 60 cm) 2. 57 3. 03 2. 47 2. 690 4900cm2 (70cm by 70cm) 3. 11 3. 04 3. 27 3. 140 After doing these pre-tests, I decided to use a range of 30cm by 30 cm and 60 by 60cm for the surface area, and therefore testing 900cm2, 1600cm2, 2500cm2, and 3600cm2 for my real experiments. I have decided to tests this range of surface areas because it gives us a large time frame in which the parachutes can fall, also if we test any parachutes that are over 3600cm2 it will take too long to tests the parachutes and do repeats for each test if say any of the results we get are outliers.

I have decided to use parachutes without structure/support because after timing how long I will take to make just one parachute, it will take too much time for us to do it seeing as it took me 15 minutes to make just one parachute and we would need to make four. Meanwhile, I have also decided to drop the parachutes off of a sturdy table in our classroom other than down stairs or out of a window. This is because if we drop it down stairs if could easily get caught and we would need someone to keep going up and down the stairs to get the parachute. Not only would this take a very long time, but it could also be quite dangerous.

I have also decided not to drop it out of a window because it could again take too long, get caught and could be dangerous to keep going up and down the stairs. Another reason why I am not going to drop the parachutes out of a window is because the wind could have an effect on how fast/ slow the parachute falls. Prediction I predict that if I increase the surface area of the parachute by a factor of 2, the velocity will decrease by a factor of 0. 2 (for example if the surface area of 1000cm2 had a velocity of 1 m/s then the surface area of 2000cm2 would be 0.

8 m/s). Hypothesis I predict this because the bigger the surface area of the parachute, the slower the velocity that it will fall. This is because there are larger surfaces for air resistance to come into contact which, and as a result slowing it down by increasing gravity’s opposing force. Equipment Name of Equipment What I Will Use it For Why I am Using this Instead of Another Piece of Equipment Black Bin Bags I will use the black bin bags to make the parachute cover where it catches the air to make the parachute slow down while falling.

I am using this rather than normal plastic bags that you get from supermarkets because they are bigger and stronger that the plastic bags. You are able to cut it to the correct shape easily. Also, plastic bags sometime have holes in the bottom where they are pulled out of a machine which could have an effect on how the parachute falls, and it would make it more difficult to work out the correct surface area. String I will use the string to attach the ping pong ball to the parachute cover made out of black bin bags. I am using string rather than thread purely because it is strong than thread, so is less likely to break during the experiments.

Ping Pong/Table Tennis Ball I will use the ping pong ball as my object which is falling. I am using this rather than a ball bearing because it is lighter and due to the mass of the ball bearing, when it falls it could damage the floor or hit someone and cause injury while it is falling. Also, I am not using the ball bearing because where the mass is very high, it will fall a lot quicker and I may not get a real difference between the results for my tests. Sticky Tape I will use the sticky tape to secure the end of the string so that they do not unravel and split.

I will also use it to make sure the string is secure to the parachute cover and the ping pong ball so that my parachute does not break during my experiments. I am going to use sticky tape rather than bluetack because It is stronger and less likely to come off. Also, bluetack can be quite expensive so it would be a waste to use it on the experiment when sticky tape is cheaper and stronger. Stopwatch I will use the stopwatch to time how long it takes for the parachute to reach the ground, so that I can then work out the velocity of the parachute. I am going to use a stopwatch because it is able to measure to 0.

1 of a second. Calculator I will use the calculator at the end of the experiments to work out the average results and to work out the velocity and the velocity average of the parachutes. I am going to use a calculator because it would be quicker and easier to work out the average results and to work out the velocity and the velocity average of the parachutes than having to work them out using mental mathematics. Meter Stick I will use the meter stick to measure out how big I need to cut the parachute to the closest mm and to make sure that all the parachute sides are straight.

I am going to use a meter stick rather than a ruler because a ruler only measure to 30cm and that is the size of the small parachute. Tape Measure I will use the tape measure to measure out the height from where I need to drop the parachutes. I am not using a meter stick to do this because it is too short to reach the ceiling from the floor. Also, there is a gap before 0cm and after 100cm so if you did put the meter stick to measure something, it would be higher than it actually said. Meanwhile, a tape measure is long enough because it goes to 4 meters long and it is flexible so we would get the correct measurement.

Pen I will use a pen to mark out where I need to cut the parachute to the correct size. I am going to use a pen rather than a pencil. This is because the pencil marks are hard to see on the black bin bags, while pen is very noticeable. Scissors I will use the scissors to cut out the parachute so that it has the correct surface area for my test. I am going to use scissors rather than a scalpel knife because we do not have big enough mats to go under the bin bag while we are cutting it so that we do not cut the surface underneath. Also, scissors are not as sharp, so are less likely to cause injury to someone.

Hole Puncher I will use the hole puncher to make a hole in each of the corners of the parachutes to attach the string to it. I am going to use a hole punch rather than a pencil or scissors to make these holes because this way they will all be the same size and will minus the same amount of surface area off of each parachute. Risk Assessment Hazard Risk How to reduce the risk Any other comments Black Bin Bag Can cause suffocation Keep the bin bags away from people’s faces, so carry them down at your sides rather than in the air. Scissors You could cut yourself or somebody else.

When walking around the room keep the scissors fold up and point the blades to the ground while gripping them with your fist. If you or somebody else does get cut by the scissors report it to the teacher who is supervising and then seek medical attention. Stools You could trip over a stool and hurt yourself. Make sure the stools and chairs are all tucked under the table. Make sure you are standing at all times during the experiment. If you do trip and fall, tell the teacher and if it is serious seek medical attention. Bags You could trip over a bag and hurt yourself.

Make sure you have either put your bag under your desk or on the coat pegs. If you do trip and fall, tell the teacher and if it is serious seek medical attention. Table You could fall off it while dropping the parachutes. Make sure the table is sturdy before you get on it and stand in the middle of the table with your arms over the edge. Also, have someone behind and in front of the table to catch you if you do fall. If any accidents do occur, seek medical attention immediately. Method 1) Draw out results tables so that while doing the experiment you can record the results and gather all the equipment needed.

2) Make sure your area you are going to work in is clear so that nothing gets damaged and so that you can have as much room as possible. Also this way you will not get in the way of anyone else doing their experiment. 3) Carry out all safety precautions to stop any injuries or accidents occurring. 4) Cut the bin bag so that it is open in one big sheet. 5) Measure out 60cm by 60cm on the bin bag using a meter stick and mark it out using a pen. 6) Cut out the square using a pair of scissors. 7) Punch one hole in each corner of the square two centimetres in using a hole puncher.

8) Cut four pieces of string all to the same length of 20cm. 9) Wrap each end of the strings in 1cm of sticky tape to ensure the string does not unravel. 10) Tie all of the pieces of string together at one end. 11) Wrap the ping pong ball in string like you would a parcel (shown below) 12) Attach the four pieces of string to the ping pong ball by cutting one piece of 3cm length string and tying both together. 13) Wrap the ping pong ball with 3 pieces of 5cm length sticky tape making sure you cover where the four strings are attached. 14) Thread one end of the four strings threw each of the holes in the corners of the parachutes.

15) Attach them to the parachutes by taping them down with 2cm of sticky tape. 16) Check that the parachute is all secure and nothing is going to fall off or break. 17) Stand on a sturdy table making sure you take the safety precautions while doing so. 18) Hold two of the parachutes edges so that it is open, and hold it to the ceiling. 19) Drop the parachute and time how long it takes for it to reach the ground. 20) Record the timing. 21) Repeats the drops three times so that you can calculate the average results and you are able to stop any outliers. 22) If there are any outliers repeat the test a further time.

23) Repeat this method for the rest of the parachutes, however to make sure you are using the same material use the parachute you just dropped to make the smaller one by cutting that and re-attaching the ping pong ball by keeping the strings the same and just add new sticky tape. Results Surface Area Time taken to reach to ground (Seconds) Test 1 Test 2 Test 3 Average 900cm2 (30 cm by 30 cm) 1. 8 2. 1 1. 9 . 1. 93 1600cm2 (40 cm by 40 cm) 2. 3 2. 6 2. 4 . 2. 43 2500cm2 (50 cm by 50 cm) 2. 9 3. 1 2. 8 . 2. 93 3600cm2 (60cm by 60 cm) 3. 7 3. 7 3. 6 . 3. 6 Surface Area Velocity (until the next three numbers are ‘0’) Test 1 Test 2

Test 3 Average 900cm2 (30 cm by 30 cm) 1. 422222222222220 1. 219047619047620 1. 347368421052630 1. 329546087440820 1600cm2 (40 cm by 40 cm) 1. 113043478260870 0. 984615384615385 1. 066666666666670 1. 054775176514310 2500cm2 (50 cm by 50 cm) 0. 882758620689655 0. 825806451612903 0. 914285714285714 0. 874283595529424 3600cm2 (60cm by 60 cm) 0. 691891891891892 0. 691891891891892 0. 711111111111111 0. 698298298298298 Surface Area Velocity (m/s) Test 1 Test 2 Test 3 Average 900cm2 (30 cm by 30 cm) 1. 422 1. 219 1. 347 1. 330 1600cm2 (40 cm by 40 cm) 1. 113 0. 985 1. 067 1. 055 2500cm2 (50 cm by 50 cm) 0. 883 0. 826 0. 914 0. 874

3600cm2 (60cm by 60 cm) 0. 692 0. 692 0. 711 0. 698 Graphs Secondary Data [7] This graph shows that as you increase the surface area, the terminal velocity of the falling object decreases. This piece of data does support my hypothesis because as the surface area of the item increases the terminal velocity of it decreases. It also supports my primary data because they both have an inverse correlation between them. Meanwhile this piece seems to curve in the middle of the data and in my primary data it is one straight line; however this could because they dropped it at a different height or the weight of the object was different.

I believe this data is reliable because it is similar to mine and came from a website where they had all of their process, equipment, everything needed to do the experiment and had a video to show you how they did it therefore I believe it is reliable. [8] I believe these results are reliable because of the source at which I got them from – the OCR Board. These results support mine because it is saying that when the surface area is smaller (THE PARACHUTE FAILS TO OPEN) the terminal velocity of it is higher since there is less air resistance coming in contact with it.

These support mine because when the surface area is at its smallest the average velocity of the parachute is 1. 329 m/s, while the largest surface area has a velocity of only 0. 698 m/s. Overall, I believe these results support mine to the highest level and are reliable because of the source from which they came from. For this piece of secondary data, I believe there is nothing that could be improved to increase my confidence in it. [9] These results show that as the surface area of the parachute increased, the time taken for it to reach the ground also increased; which supports my hypothesis and coincides with my primary data.

I believe this data is accurate because the differences are all very small and none of the ranges overlap meaning that there is a real difference between the results. I believe that this secondary data is reliable because it came from a class member and I was watching while she did the experiment to make sure none of the results got altered and she did everything to the method she had written down. Evaluation of Method One of the problems I found in my experiment was that reaction times added time to the ‘time taken to reach the ground’ as they are dependent on the reaction time of the person using the stopwatch.

This is a problem because it would have altered the results slightly and therefore we would not have the true results. To resolve this problem, next time before we do the experiment we could test to see who has the quickest reaction time and they could be the person to time the experiment. This way we could get the result to the most accurate time we can. Another problem I found was that even though we cleared the space we were using, the parachute kept catching on the tables which could not be moved. Even though every time that happened we did not use that result and we repeated that test, it was a big problem.

This is because is added unnecessary time on our experiment and seeing as we only had a short while to complete the experiment it was a big problem. Next time, I would change the location of the experiment to a place where there would be no obstacles. A further problem I found was that the sides of the parachute were not cut straight causing the symmetry of the parachute to be wrong affecting the flight path; this could have also been the reason why the parachute did not fall straight down and caught on the tables; which would alter the timings and the distance that the parachute travelled.

To resolve this, next time I would use a scalpel knife to cut the bin bag even though a chose against it before we did not have big enough mats to go under the bin bag while we were cutting it so that we do not cut the surface underneath. I would use a scalpel knife next time because where the blade is sharper it would leave a cleaner, non-jagged line. I would also use a ruler to mark out the line and then run the scalpel down the side of the ruler to be certain that the line was straight. Another problem I found is that we did not keep the weight of the parachutes the same.

We keep all the materials the same; however since the parachute was getting smaller each time, it would decrease in weight. This would then have been changing two different variables rather than just the one. To change this, next time I would weigh the parachute first and then each time we decreased the size of the parachute, add some weight to the ball on the end to make it the same weight as before. The final problem I found with my experiment is that drafts, wind or people walking past may have caused excess movement of the parachutes thus causing the path to be diagonal rather than straight.

This would have affected both the time taken and distance travelled. Next time I would make sure all the windows and doors in the room were shut; however not locked in case of a fire; and made sure only the necessary people were in the room, this way less movement would be made and the parachute would be able to fall straighter. All of these problems altered either the time it took for the parachute to reach the ground, the distance the parachute travelled, or both. This is all a problem in itself because if the amount of time taken was changed and was not at its true value, then our results are inaccurate.

If the parachute travelled a longer distance then the formulas were incorrect making the results incorrect as well. Next time, I would carry out all of the changes above: making sure the sides of the parachute were straight; that there was no excess movement; that we were in an obstacle free location; that the person timing the parachute had the quickest reaction time; and that the parachute all weighted the same. Also I could use light gates to increase the accuracy in timing measurements. Light gates are simple optical circuits that have an opening between an emitter and receiver.

If the path between the two is interrupted, a signal is sent to a computer or other data recorder. Light gates are typically used for timing and detection. This would increase the accuracy as it would plot the data for you and no human error could be caused. Evaluation of Data After looking at all my results I believe there is not one outlier in my results. I believe this because all of the results for one parachute are very similar and none of the results for any of the parachutes overlap. Degree of Scatter Table (seconds)

Surface Area of Parachute Highest Time (s) Lowest Time (s) Difference (s) (highest-lowest) Repeatable (yes/no) 900cm2 (30 cm by 30 cm) 2. 1 1. 8 0. 3 Yes 1600cm2 (40 cm by 40 cm) 2. 6 2. 3 0. 3 Yes 2500cm2 (50 cm by 50 cm) 3. 1 2. 8 0. 3 Yes 3600cm2 (60cm by 60 cm) 3. 7 3. 6 0. 1 Yes Degree of Scatter Table (velocity) Surface Area of Parachute Highest Velocity (m/s) Lowest Velocity (m/s) Difference (m/s) (highest-lowest) Repeatable (yes/no) 900cm2 (30 cm by 30 cm) 1. 422 1. 219 0. 203 Yes 1600cm2 (40 cm by 40 cm) 1. 113 0. 985 0.

128 Yes 2500cm2 (50 cm by 50 cm) 0. 914 0. 826 0. 088 Yes 3600cm2 (60cm by 60 cm) 0. 711 0. 692 0. 019 Yes I believe my method was very accurate and repeatable because after looking at these ‘degree of scatter’ tables you can see that all of the results have very small differences between them meaning that the results were very close to the true value. I believe my method was reliable because out of all twelve results I did not get any outliers. Surface Area Test 1 Test 2 Test 3 Average 900cm2 (30 cm by 30 cm) This result is 0.

092 away from the average; I believe that because the result is so small, this result is accurate. This result is 0. 111 away from the average; this difference is the largest out of all the results and their corresponding average, however this result is still very small and therefore accurate. This result is 0. 017 away from the average; I believe that this result is accurate because the difference is very small and I can therefore put a lot of confidence in it. All of these results are what I consider to be accurate and reliable.

Also the difference between the highest and lowest result is 0. 203. Although this result is very small it is the largest out of the difference between a singular parachute’s results, therefore I am not as confident in these results as I am with the others. 1600cm2 (40 cm by 40 cm) This result is 0. 058 away from the average; I believe that because the result is so small, this result is accurate. This result is 0. 07 away from the average; I believe that because the result is so small, this result is accurate.

This result is 0. 012 away from the average; I believe that this result is accurate because the difference is very small and I can therefore put a lot of confidence in it. All of these results are what I consider to be accurate and reliable. Also the difference between the highest and lowest result is 0. 128. This result is not as small as some of the other but I can still say that these results are repeatable and I can put a lot of confidence in them. 2500cm2 (50 cm by 50 cm) This result is only 0.

009 away from the average; because of the result being extremely small I can put all my confidence in this result being as accurate as possible. This result is 0. 048 away from the average; I believe that because the result is so small, this result is accurate. This result is 0. 04 away from the average; I believe that because the result is so small, this result is accurate. All of these results are what I consider to be accurate and reliable. Also the difference between the highest and lowest result is 0.

088. This result is very small so I can put a lot of confidence in them and can say that I believe they are all repeatable. 3600cm2 (60cm by 60 cm) This result is only 0. 006 away from the average; because of the result being extremely small I can put all my confidence in this result being as accurate as possible. This result is only 0. 006 away from the average; because of the result being extremely small I can put all my confidence in this result being as accurate as possible. This result is 0. 0

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