Aaaphys.thread
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Physics Experiment Thread Strength Name: Date Started: December 11, 2013 Section/rade: rade 10 ! "#$ Date %inished: ro&p : '(Despicab)e*Th&rs+ Introduction - .orce that ca&ses a distortion on the si e or shape o. abody is ca))ed a distorting force. - body is e)astic i. it ret&rns to its origina) si e or shape a. distorting .orce is remo ed+ E ery materia) has its o n partic&)ar e)asticity+ %o examp)e, a stee) ire is di c&)t to stretch, b&t its e)asticityis high+ - r&bber b can be easi)y strtched, b&t a.er being stretched se era) times it i)) no )onger ret&rn to its origina) si e+ There is a )imit to the magnit&de o. the distorting .orce hich may be app)ied i. the body is to ret&rn to its origina) condition+ This is ca))ed the elastic limit. amo&nt o. distorting .orce goes beyond this )imit, it i)) ca&se a permanent distortion or e en brea4 + n th&s experiment yo& i)) determine the strenght o. three di5erent brands o. threads+ The thread is stretched and experiences a tensi)e strain+ The .orce acting on the thread is ca&sed by the eight o. the )oad (a p)astic c&p and sand hanging .rom it+ This is the distorting .orce hich is a meas&re o. tensi)e stress+ The greater the distorting .orce app)ied itho&t brea4ing the thread, the higher its tensi)e strenght+ The minim&m .orce that i)) ca&se the thread to brea4 is ca))ed the ultimate strength. Objective To compare the strenght o. three di5erent brands o. se ing thread Materials Sand P)astic c&p 3 di5erent brands o. se ing thread o. the same diameter ron stand 6a)ance sca)e
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Transcript of Aaaphys.thread
PhysicsExperimentThread Strength
Name: Date Started: December 11, 2013Section/Grade: Grade 10 MQH Date Finished: Group : 4(Despicable-Thurs.)IntroductionA force that causes a distortion on the size or shape of abody is called a distorting force. A body is elastic if it returns to its original size or shape after a distorting force is removed. Every material has its own particular elasticity. For example, a steel wire is difficult to stretch, but its elasticityis high. A rubber band can be easily strtched, but afer being stretched several times it will no longer return to its original size.There is a limit to the magnitude of the distorting force which may be applied if the body is to return to its original condition. This is called the elastic limit. If the amount of distorting force goes beyond this limit, it will cause a permanent distortion or even break . In thus experiment you will determine the strenght of three different brands of threads. The thread is stretched and experiences a tensile strain. The force acting on the thread is caused by the weight of the load (a plastic cup and sand) hanging from it. This is the distorting force which is a measure of tensile stress. The greater the distorting force applied without breaking the thread, the higher its tensile strenght. The minimum force that will cause the thread to break is called the ultimate strength.
Objective To compare the strenght of three different brands of sewing threadMaterials
SandPlastic cup3 different brands of sewing thread of the same diameterIron stand Balance scale Iron ring or clamp
Procedure 1. Tie one of a 30 cm long thread to an iron ring (or clamp) attached to an iron stand.2. Hang a small plastic cup to the other end.3. Pour in sand very slowly and stop as soon as the thread breaks.4. Weigh the plastic cup and sand in the balance scale. Express the weight in newtons. This is the force that caused the string to break.5. Repeat procedures 1 to 4 using the other brands of thread.6. Make three trials for each brand.7. Compare the average forces. Account for the difference, if any.
Data and Results
BrandTrial 1Trial 2Trial 3Trial 4N
a. Astra
b. Earth
c. Apple
COMPUTATIONS:
Generalization
Application
1. What is meant by ultimate strenght?
2. Why do some solids lose their original size or shape when stretched or twisted?
3. Of what importance to industry are the concepts of stress and elastic limit?
