Crunchie Bones Essay Example for Free

Crunchie hit the keeps EssayThe aim of this experiment is to test whether or not a Crunchie bar could be use as a drop replacement. If this were possible the crunchie would energise to be strong enough to support the patients conduct style. The Crunchie bar will be used to replace a leg bone. After the experiment I will calculate the ultimate breaking emphasis of the Crunchie and thence compare this to the ultimate breaking song of a leg bone. I will calculate the tense by exploitation the formulationThe mechanism is going to be set up as followsI will tighten both of the G-clamps by 90 at the same time, then I will read off the impression on the dial of the scales. I will read the dial from directly above otherwise parallax whitethorn occur. I am using three crunchies at the same time, as this will be more(prenominal) reliable. To solve the measurements accurate I will calibrate the scales after the crunchies and wooden boards have been put on to it. I will ensure that the G-clamps are placed in the middle of the blocks so that the pressure off these blocks is airing over all of the disallow, and not just on one side. The safety aspect of this experiment is that the G-clamps may fall off and cause an accident.ResultsDegree turns ( )Force in Newtons (N)9058.8180147.0270264.6360431.2450617.4540833.06301038.87201185.88101176.09001127.09901097.610801097.611701097.612601097.613501097.614401097.6I have, as accurately as possible, measured the surface area of one crunchie, the measurements were 140mm x 25mm= 3500mmTo use the stress formula the surface area privations to be in m , to get this I will3500 x 1000000= 0.0035mAs I have used three crunchie bars I will need to times the above range by 30.0035 x 3= 0.0105mUsing the above results dishearten I have constructed a graph. As it and the results table shows the crunchie bars held up against a great force, then went the force reached 1190.0N, the crunchie bars crumbled. This meant the up ward force from the crunchie bars went and the force dropped down to1097.6N this force go on when the G-clamps were conductd to be turned.CalculationsBy doing the following calculations I will determine the ultimate breaking stress of the crunchie bars for one leg. assay ( ) = force (f)Area (A)Stress ( ) = 1190.0 N0.0105 mStress ( ) = 113333.3 Pa= 11 x 10 PaDue to inaccuracies of the scales I am going to calculate the upper limit and minimum values of the force and then calculate the breaking stress due to these differences.Maximum force = 1200 NMinimum force = 1180 NMaximum Stress = 1200 N0.0105m= 114285.7 Pa (1dp)= 1.14 x 10 PaMinimum Stress = 1180 N0.0105m= 112380.9 Pa (1dp)= 1.12 x 10 PaI have accounted for the inaccuracies of the scales and of the turning of the G-clamps by drawing error boxes on the graph. The size of the error boxes is 20N x 36 . bring forward calculations will determine whether or not the crunchie bar would be a competent replacement for a leg bone.Average mas s of human = 60kgWeight = mass x gravity= 60 x 9.8= 588 NArea of crunchie bar = 0.0105m Area for two legs 0.0105 x 2= 0.021mStress = FA = 600N= 600N 0.021m0.0105m = 28571.4 (1dp)= 2.8 x 10 PaStress = 57142.9 Pa (1dp) (1 leg)= 5.7 x 10 PaBy using question eight from the section supererogatory Part Surgery in the Salters Horners Advanced Physics book I can see that the crunchie bar would not be able to be used as a bone replacement. This is because the value given in the book for stress on the leg bone when someone standing still is 10 Pa and so is bigger than the 2.8 x 10 Pa, so the crunchie would shatter when under this stress.When investigating further and by using question nine from the section Spare Part Surgery in the Salters Horners Advanced Physics book I found that there is a bigger value for stress when the person moves or in the case of question nine, jumps off a wall. The below calculations show that the crunchie bar would be unable to with stand the stress of the patien t moving heyday of wall = 1.5mTime taken = 0.1sGravity = 9.8ms = 9.8NkgMass = 70kga = vt= 5.420.1= 54.2 msF= ma= 70kg x 54.2ms= 3.80 x 10 NCalculations for crunchie barsArea of both legs = 60 x 10 m Area of crunchies = 0.0105mCalculations for bone Man lands on two legs = 0.0105 x 2Stress = F = 0.021mAStress = F= 3.80 x 10 N A60 x 10 m = 3.80 x 10 N= 6.3 x 10 Pa 0.021m= 18095238.1 Pa= 1.8 x 10 PaThese calculations show that the crunchie bar could not with stand the stress when the patient moved. This is shown in the calculations because the value of stress on the crunchie bars when put in this situation is greater than that of the leg bones. Therefore the crunchie bars would break.Overall this experiment has shown that a crunchie bar could not be used as a suitable bone replacement as it would not be able to with stand the ultimate breaking stress of a person if they were standing still or if the person was moving.If I had more time to continue this experiment I would make a piece of apparatus, like a protractor, that enabled me to measure the degree turns that I made when turning the G-clamps making my measurements more accurate. Using the apparatus I could also make more turns such as 45 turns as well as 90 turns.