Friday, January 24, 2020

Physics of Skydiving :: physics skydive

Acceleration..... Galileo demonstrated that an object falling only under the influence of gravity will experience a constant acceleration, i.e.., it gains the same amount of velocity for every additional second that it falls. (5) On earth this amounts to 32.14 ft/sec/sec, meaning that it increases its downward velocity by 32.14 ft/sec for each second that it falls. If acceleration is constant, then it follows that the downward velocity V an object experiences at any time t after the start of the fall is given by: V=g t where V=velocity (m/sec) t=time (sec) g=acceleration due to gravity One can also show that the distance d fallen after time t is: d= 1/2 gt^2 where d=distance fallen (ft) g=12.54 ft/sec/sec for Mars t=time (sec) Furthermore, Galileo discovered that this acceleration is independent of the body's mass, but dependent only on the strength of gravity on the planet. So, in the absence of an atmosphere, heavy things don't fall faster than light things, but at moderate to large velocities even a thin atmosphere can have a significant effect on a falling body's motion due to the effects of aerodynamic drag. (5) Freefall... When in freefall, a skydiver with arms and legs outstretched falls at about 120 mi/hr, with the arms in and the body in more of a diving position, the skydiver can reach speeds of up to 200 mi/hr. At this speed, many people believe that it is impossible to breath. Well, it is not impossible, but the truth is, you don't even need to breath because enough oxygen is absorbed through your skin to provide the blood cells with the required oxygen. This is also why jumpers do not jump on cloudy days or when they might risk going through clouds. The moisture in the clouds can condense on their exposed skin surfaces preventing the absorption of the necessary oxygen resulting in suffocation. (2) How fast do you fall? When you leave the aircraft, you are moving horizontally at the same speed as the aircraft, typically 90-110MPH. During the first 10 seconds, a skydiver accelerates up to about 115-130MPH straight down. (A tandem pair uses a drouge chute to keep them from falling much faster than this). It is possible to change your body position to vary your rate of fall.

Thursday, January 16, 2020

The Fencing Problem

A farmer has exactly 1000 metres of fencing; with it she wishes to fence off a plot of land. She is not concerned about the shape of the plot, but it must have a perimeter of 1000m. So it could be or anything else with a perimeter (or circumference) of 1000m What she does wish to do is fence off the plot of land which contains the maximum area. Investigate the shape, or shapes of the plot of land which have a maximum area. Throughout this investigation I will check that the perimeter is 1000 meters by finding the total of all the outer sides. Also I will use refining as a way of finding the maximum area. When I talk about using the maximum area of the previous table the maximum area of each table will be highlighted. Rectangles The first shape I will test will be a rectangle. Having been told that the perimeter must be 1000 meters I will find the areas of three rectangles, each with different lengths of sides, making sure that the perimeter is kept the same. To calculate the area I will use the formula LENGTH x WIDTH = AREA or Area = lw. Rectangle A: l = 450m w = 10m Area = 450 x 10 Area = 4500m2 Rectangle B: l = 300m w = 200m Area = 300 x 200 Area = 60000m2 Rectangle C: l = 100m w = 400m Area = 100 x 400 Area = 40000m2 Having carried out the above calculations I will create a spreadsheet with formulae to carry out more calculations. The headings will consist of Length, Width, Perimeter and Area. Under length there will be a variable number (less than 500 and greater than 0). The first formula will be put under the width heading. The width will be calculated by taking the length away from 500. This will guarantee the perimeter to be 1000m. The formula will be =500-B2 where B2 is the cell in which the length is. To double check that the perimeter is 1000m under the perimeter heading there will be another formula. This will be =(B2+C2)*2 where B2 is the length and C2 is the perimeter. It will be multiplied by 2 because the answer in the brackets would be just the total of two sides and not all four. Finally under the area heading there will be a formula. This will be =B2*C2 where B2 is the length and C2 is the width. This formula is the same as the one used previously to calculate the area of a rectangle. The formulas and headings will be entered in as shown in the table below. Length (m) Width (m) Perimeter (m) Area (square m) 490 =500-B2 =(B2+C2)*2 =B2*C2 Having entered the correct information I will be able to calculate the areas of many different sizes of rectangles with a perimeter of 1000m. I can do this in Microsoft Excel by dragging the formula boxes down, thus duplicating them but allowing them to refer to different lengths. (Please see tables and graphs [Fencing Problem for Rectangles]) To start with I used my spreadsheet to find the area of a few rectangles within the range of 1m and 499m.I then plotted a graph showing length against area. It showed a perfect curve. I decided that the line of symmetry of this curve would help to find the length that would give me the maximum area. I found the line of symmetry to be along the 250m mark on the x axis of the graph. Hypothesis I predict that the length of a rectangle that will give me the maximum area will be 250m. I have decided this having found the line of symmetry on the graph. Poof (Please see tables and graphs [Fencing Problem for Rectangles]) To prove my hypothesis I refined my search around the maximum area of the first table and then the second table, followed by the third table and so on. Eventually I found that, even to 1 decimal place above or below 250m that, the maximum area was given by rectangle of sides 250m by 250m. This shows that a square gives the maximum area for a rectangle. Isosceles Triangles The second shape that I will test will be an isosceles triangle. Having carried out tests for a rectangle I am going to see whether the maximum area will be bigger, smaller or the same as that of a rectangle. I am also going to find out whether the number of sides affects the results and whether there are any similarities in results to a triangle. This will help me find the shape that gives the maximum area. As previously for rectangles I will test some different sized isosceles triangles that have an area of 1000m. The formula for the area of a triangle is BASE x HEIGHT divided by 2 or bh/2. I cannot find the area without knowing what the height of the triangle is. To find the height of the triangle I must use Pythagoras. This states that for a right-angled triangle a2+b2=c2 or the square hypotenuse is equal to the sum of square of the other two sides. Therefore to find the height I must split the triangle in half and then use half of the base to help me find the height. The square height will therefore be equal to the square of the hypotenuse minus the square of half the base. In the below examples b = base, s = one equal side of the triangle and h = height. Triangle A: b = 500m s = 250m b/2 = 250m h = 2502-2502 h = 0m Area = 250 x 0 / 2 Area = 0m2 Triangle B: b = 400m s = 300m b/2 = 200m h = 3002-1002 h = ?50000m h = 223.6068m Area = 400 x 223.6068 / 2 Area = 44721.35955m2 Triangle C: b = 200m s = 400m b/2 = 100m h = 4002-1002 h = ?150000m h = 387.29833m Area = 200 x 387.29833 / 2 Area = 38729.38466m2 After completing the above tests I will create a spreadsheet with formulae to carry out more calculations. The headings will consist of Base, 1 equal side, Perimeter, Height and Area. Under the base heading there will be a variable number between 1 and 500. The first formula will be used to calculate the length of one equal side of the isosceles triangle. The formula will be =(1000-B2)/2 where B2 is the base. It will be divided by 2 because 1000-B2 would give the sum of the two equal sides together. As previously , for the rectangles, there will be a formula to check that the perimeter is 1000m. This will be the base plus, one equal side multiplied by two or =B2+(C2*2). The main formula in this spreadsheet will be the one used to find the height. In a spreadsheet there are codes that represent calculations carried out. These are put at the front of the formula and the substitute for square root is SQRT. So my formula will be the square root of 1 equal side squared, minus half the base squared. However before entering my formula I found out that using the power sign (^) doesn't give accurate results and in order to square numbers I must multiply the number by itself instead of using such a sign. Therefore the formula entered into the spreadsheet will be =SQRT((C2*C2)-((B2/2)*(B2/2))) Finally under the area heading there will be a formula. This will be =(B2*E2)/2 where B2 is the base and E2 is the height. This formula is the same as the one used previously to calculate the area of a triangle. The formulas and headings will be entered in as shown in the table below. Base (m) 1 Equal Side (m) Perimeter (m) Height (m) Area (square m) 200 =(1000-B2)/2 =B2+(C2*2) =SQRT((C2*C2)-((B2/2)*(B2/2))) =(B2*E2)/2 Having entered the correct information I will be able to calculate the areas of many different sizes of isosceles triangles with a perimeter of 1000m. I can do this in Microsoft Excel by dragging the formula boxes down, thus duplicating them but allowing them to refer to a different base. (Please see tables and graphs [Fencing Problem for Isosceles Triangles}) As before I entered a range bases between 1m and 499m. I then plotted a graph of base against area and found that unlike the results for a rectangle there wasn't a perfect curve in order to find the line of symmetry, to aid my search. However I could tell that the maximum area would be given by a triangle with a base between 300m and 400m Hypothesis I predict that the maximum area will be given by a triangle with equal sides. I have decided this because the maximum area for a rectangle was given by a square and that my graph shows that the base must be between 300m and 400m. For a triangle with equal sides and a perimeter of 1000m the base would be 333.33†¦meters. Poof (Please see tables [Fencing Problem for Isosceles Triangles}) To prove my hypothesis I refined my search around the maximum area of the first table and then the second table, followed by the third table and so on. Eventually I found that, to 2 decimal places, the maximum area was given by a triangle of equal sides which is 333.33m to every side. This shows that an equilateral triangle gives the maximum area for a triangle and this proves my hypothesis right. Regular Polygons Having tested isosceles triangles and rectangles I found that regular sided shapes give the maximum area. I know this because the maximum area of an isosceles triangle is given when the sides are each 333.33m. The maximum area given by a rectangle is give by a square with 250m sides. I have also that as you increase the number of sides the area increases because the maximum area for a rectangle is 62500m2, and the maximum area for an isosceles triangle is 48112.52243m2. As a result of these findings I am going to test regular sided polygons. Having split the pentagon into isosceles triangles and then into right angled triangles I can now find the area. I know that the base of the triangle is 100m however I do not know the height. Before finding the height I must work out what the internal angle is. To find this I will divide 360 by the number of right-angled triangles (in this case 10). I can now tell the following about the triangle: – I can now use Trigonometry to find the height of the triangle. SOH CAH TOA I know what the opposite is and the angle, and I want to know what the adjacent is. I will therefore use the formula TAN=Opposite/Adjacent. Therefore Adjacent=Opposite/TAN. So the height in metres will be: Height = 100/TAN36 Height = 137.638192m Area of 1 Isosceles Triangle = (200*137.638192)/2 Area of 1 Isosceles Triangle = 13763.819205m2 Area of Pentagon = 13763.819205*5 Area of Pentagon = 68819.09602 m2 After completing the above tests I will create a spreadsheet with formulae to carry out more calculations. The headings will consist of Number of Sides, 1 Equal Side, Perimeter, Internal Angle of 1 Triangle, Half Angle, Height (of internal isosceles triangle), Area of 1 Triangle and Total Area. Under the first heading (Number of Sides) there will be a variable, whole, number between 3 and as higher number as desired (e.g. 30). Under the second heading there will be a formula to calculate the length of one equal side. The formula will be =1000/A3 where A3 is the number of sides. As in all the other tests there will be a formula to check that the perimeter is 1000m. This will tell me if I have made an error in any of the previous cells. So far so good, however before I continue I must point out that a computer spreadsheet doesn't work in degrees to measure angles. It measures in radians where a complete rotation is 2?. Also ? is represented by PI() in a spreadsheet. So instead of using 360 in my formula under the Internal Angle of 1 Triangle heading I will use 2*PI()/A3 where A3 is the number of sides. Under the Half Angle heading there will be a formula that will be =D3/2 where D3 is the internal angle of one triangle. This gives the internal angle of 1 right-angled triangle. My main formula will go under the Height heading and it will use Tan which is substituted by TAN in a spreadsheet. It will be =(B3/2)/TAN(E3) where B3 is 1 equal side and E3 is the angle inside a right-angled triangle. The area of one isosceles triangle will be calculated using the formula =(B3*F3)/2 where B3 is one equal side and F3 is the height. Finally the total area will be calculated by multiplying the area of one isosceles triangle by the number of sides. The formula entered will be =G3*A3 where G3 is the area of one triangle and A3 is the number of sides. The formulas and headings will be entered in as shown in the table below. Number 1 Equal Side Perimeter Internal Angle Half Angle Height Area of 1 Triangle Total Area of Sides (m) (m) of 1 Triangle (rad.) (rad.) (m) (square m) (square m) 5 =1000/A3 =B3*A3 =2*PI()/A3 =D3/2 =(B3/2)/TAN(E3) =(B3*F3)/2 =G3*A3 Having entered the correct information I will be able to calculate the areas of many regular polygons with different numbers of sides and with a perimeter of 1000m. I can do this in Microsoft Excel by dragging the formula boxes down, thus duplicating them but allowing them to refer to a different number of sides. Hypothesis I predict that as you increase the number of sides the area increases because the maximum area for a rectangle is 62500m2, and the maximum area for an isosceles triangle is 48112.52243m2. Proof (Please see graph and table [Fencing Problem for Regular Polygons]) Used my spreadsheet to calculate the areas of polygons with sides ranging from 3 to 30. The polygons with 3 and 4 sides were used to test that my formula worked correctly. I plotted a graph showing the number of sides against the area and found that, as predicted, as the number of sides increased so too did the area. Circle After my findings from carrying out tests on regular polygons I have decided to test circle. I have decided this because as the number of sides of a regular polygon increase so too does the area and a circle is an infinitely sided regular polygon. Hypothesis I predict that a circle will give the largest area because of my tests on regular polygons. I also predict that the maximum area given will be pretty close to that of a regular polygon with 30 sides (79286.37045m2) because of the curve on the graph plotted for the regular polygon section. To find the area of a circle I will be required to use the formulae 2?r and ?r2. The circumference must be 1000m and before finding the area I need to find the radius. Radius = (1000/2)/? r = 500/? r = 159.1549431m Area = ?*159.15494312 Area = 79577.47155m2 To complete this in a spreadsheet under the circumference heading I would enter 1000. Under the radius heading I would use the formula =(C2/2)/PI() where C2 is the circumference. Finally under the Area heading I would enter the formula =PI()*(D2*D2) where D2 is the radius. The headings and formulas will be entered as shown in the table below. Number of Sides Circumference (m) Radius (m) Area (square m) Infinite 1000 =(C2/2)/PI() =PI()*(D2*D2) Formula – 2?r (Circumference/2)/? ?r2 Proof Number of Sides Circumference (m) Radius (m) Area (square m) Infinite 1000 159.1549431 79577.47155 The table above clearly proves my hypothesis correct. The working out also proves my hypothesis correct. Conclusion Having completed the spreadsheet table I can conclude that a circle gives the maximum area and that the result was close to that given by a 30 sided regular polygon. A circle provides the maximum area possible for fencing of length 1000m. The maximum area possible is: – 79577.47155m2

Tuesday, January 7, 2020

The New Rules Of A Project Manager Essay - 1577 Words

Meredith (2006) mentioned that selecting a project manager is one of the two most important decision concerning the project. He mentioned the project manager should have credibility and sensitivity. However, in other books mentioned that PM not only should have credibility and sensitivity but also vision, courage, integrity, and discipline Visioner John P. Kotter described a project without vision is a region that is unknown which is a stretch of unmapped future. In his book The New Rules: How to Succeed in Today s Post Corporate World, he mentioned that the main destruction is there is no any vision from PM. Benis and Nanus, (1997: 19) defines vision as: Something that articulates a view of a realistic, credible, attracttive future for the organization, a condition that is better in some important ways than what now exists Furthermore becah (1993) said that the vision is a general formulation of the desired state at the end of the plan period to achieve the goals that may be achieved within a certain period. Visionary leader is a leader whose in running the organization s activities emphasize the vision that has been set together from planning, implementing, monitoring, and evaluating as a manifestation of the organization. A PM must be visionary because it can foster the commitment of its employees. One easy way to visualize the vision is by imagining what we want to achieve an organization in the future. PMs who are on a mission with his team will strive inShow MoreRelatedThe Main Tasks Of A Financial Manager1549 Words   |  7 Pagesexerts a significant impact on individuals as well as companies nowadays. Knowledge about finance fills so many books to equip financial managers to create more benefits for the company. As a financial manager, one primary duty is maximising the wealth of the firm by making correct decisions. This report will focus on the three main tasks of a financial manager, name investment decision, financing decision and dividend decision. Firstly, we will state our understanding of these terms in detail. ThenRead MoreDefine an â€Å"Efficient Market† and the Three Forms of Market Efficiency. Explain How Each of the Forms Differs from a Perfect Market. Define Arbitrage and E xplain What Kind of Information Is Needed for You to Obtain853 Words   |  4 PagesForm will appear when all information is publicly available, including the historical price information. The price should rise at once when the news release and no chance for profit when the investor analysis the information. The Strong Form appears in which the price reflects all information publicly or privately on market. Secret news or insider’s news is useless for investors to earn profit in this form. Arbitrage will generates profit from the rationally purchase and sale of similar stocksRead MoreEssay on project management1748 Words   |  7 Pagesï » ¿ Project Charter Colorado Spring Welcome Home Parade QI CHEN Project Management January 24, 2015 Abstract This project charter is planned to help O’Donnell O’Donnell LLP who will lead the project management team take place the parade smoothly. This parade for welcoming home troops will be organized in Colorado Spring which has a long history of military. This project charter’s goal is making sure project management team and sponsorsRead MoreProject Selection Risk Project Risk1052 Words   |  5 PagesRunning head: PROJECT SELECTION RISK 1 Project Selection Risk Natasha Bing Grantham University PROJECT SELECTION RISK 2 Abstract With any project, it always needs to be completed within a certain time period, and most often times it will acquire various costs to includeRead MoreAnalysis Of Google s Project Oxygen772 Words   |  4 PagesGoogle’s Project Oxygen has developed a new perspective in modern management using their eights rules of thumb, as a substitute to knowledgeable workers to deal with their managers in the typical command-control approach, making organization of most businesses in a skeptical situation, especially when it comes to sophisticated entrepreneurs ,. The way Google used their own data-driven approach for reasoning, and applying it into their human resource system ,was the key point to accommodate theRead MoreProject Management Structure Paper862 Words   |  4 PagesRunning head: PROJECT MANAGEMENT STRUCTURE PAPER Project Management Organizational Structures Paper University of Phoenix MGT 437- Project Management Roy Chuang December 2, 2012 Project Management Organizational Structures Paper A project organization is a framework of rules and regulations that companies use to facilitate the harmony and finishing point of project activities. Its foremost objective is to generate a atmosphere that will encourage relations betweenRead MoreThe Success Of New Managers1239 Words   |  5 PagesGain experience. New managers tended to strictly follow rules, because that is how they succeeded as nurses and doctors. However, this was not ideal behavior for a manager. It was precisely their ability to apply their expertise in unique ways to unique situations that brought the most value to their work (Cathcart Greenspan, 2013). Andron stated this another way, â€Å"strictly-regulated organizational cultures will never be creative and innovative, thus, companies nurturing such organizational culturesRead MoreChallenges Of Global Project Management1629 Words   |  7 Pages Global Project Management is one of the most important topics when dealing globalization of an organization. It is the most significant part when trying to accomplish a goal or build a strategy for a new product or service in a new region. There are many characteristics for Global Project Management. Some of those characteristics will lead to advanced achievements. Global Project management can be defined through a framework that will simplify all negative indicators and will help lead organizationsRead MoreOffice Management Principles Essay1552 Words   |  7 Pagesand objectives. The office manager is an individual who is concerned with planning, organizing and controlling all aspects of management that are within the office of an organization (Buhler, 2008). This may include coordination, preparation of records, controlling communication, supervision and overseeing all the operations within the office. In order to ensure there is a smooth flow of all activities within the office, the administration should follow a set of rules that govern the smooth runningRead MoreOutline Of A New Plastic Product1176 Words   |  5 PagesProject Name: Product #368DJ Amendment History: CR Document Version Approval Date Modified By Section, Page(s)and Text Revised Purpose: The purpose of the project is to make a new plastic product which is better than the previous product in terms of: more environment friendly, causing less pollution, affordable price and long life. There were some problems with the previous products of DJ Plastics, as their containers were very large and they were not efficient as required by the customers