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- Thread starter Husayn
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Husayn
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Another one:
Fibre optic cable uses Snell's Law and a refractive index to transmit the data as light. The refractive index of the outer cladding is much higher than that of the inner cladding, causing the light to reflect internally and continiously along the inner path of the cable. A modulator converts the original electrical signal into light at the beginning of the path, and a demodulator re-converts the light signal into electricity at the end of the path.
Fibre Optics cables have replaced copper due to their ability to transmitt higher amounts of data. They are also cheaper, do not suffer from interference and are not a fire hazard.
Fibre optic cable uses Snell's Law and a refractive index to transmit the data as light. The refractive index of the outer cladding is much higher than that of the inner cladding, causing the light to reflect internally and continiously along the inner path of the cable. A modulator converts the original electrical signal into light at the beginning of the path, and a demodulator re-converts the light signal into electricity at the end of the path.
Fibre Optics cables have replaced copper due to their ability to transmitt higher amounts of data. They are also cheaper, do not suffer from interference and are not a fire hazard.
fakingtheday
Member
Good answer for fibre optics.
Lifting devices: good old medium carbon steel because it has reslience and adequate yield strength. These are tested using a tensometer test and by observing the area under the straight line section for reslience and the peak of the straightline section.
Lifting devices: good old medium carbon steel because it has reslience and adequate yield strength. These are tested using a tensometer test and by observing the area under the straight line section for reslience and the peak of the straightline section.
fakingtheday
Member
Yes i am; and no resilience is the ability of a material to withstand PLASTIC deformation and return to its normal state. I can't stress enough that it resists plastic/permanent deformation.
fakingtheday
Member
not neccessarily. Reslience is the area under the straight line section. You can have something that endures a huge load but if it won't extend you don't have a resilient material.
fakingtheday
Member
Yep, in a nutshell anyway. GOod luck for the exam.
fakingtheday
Member
14 days till all my exams are over. HAHA. So aiming for top 5
fakingtheday
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Last exam is General Maths, i dropped from 2U but i knew all the maths for Engineering luckily anyway. English Adv. Geo, Engo, D&T. Best. TimeTable. Evar.PimpPyro said:
Husayn
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OK another one:
Steel - Strong tensile and compressive strengths. It is however susceptible to corrosion, although if treated properly this can be mostly avoided.
Hardwood - Strong in tension/compression. Susceptible to insect attack/decay - but if treated properly this can be mostly avoided. Can catch fire.
Reinforced Concrete - Appropriate tensile/compressive strengths. Susceptible to concrete cancer - and once this begins it is difficult if not impossible to stop. Porosity perhaps (due to imperfect concrete pour!?!).
Steel - Strong tensile and compressive strengths. It is however susceptible to corrosion, although if treated properly this can be mostly avoided.
Hardwood - Strong in tension/compression. Susceptible to insect attack/decay - but if treated properly this can be mostly avoided. Can catch fire.
Reinforced Concrete - Appropriate tensile/compressive strengths. Susceptible to concrete cancer - and once this begins it is difficult if not impossible to stop. Porosity perhaps (due to imperfect concrete pour!?!).
PimpPyro
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Wood?!?!? + Electrical conductivity
I have read that wood is relatively weak in compression because the wood fibres buckle... Anyone else concur? Also you could mention about the conductivity of the different materials, we are walking about electricity here. Especially in high power transmissions and acting as lightning rods (protecting the cables)
I have read that wood is relatively weak in compression because the wood fibres buckle... Anyone else concur? Also you could mention about the conductivity of the different materials, we are walking about electricity here. Especially in high power transmissions and acting as lightning rods (protecting the cables)
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Husayn
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Well, wood is used for power poles is it not?
Wood is good in compression, although I suppose it depends what type of wood. I just assumed that hardwood is good in compression.
And yeah conductivity is good, steel wouldn't be useful as a power pole because it might go live.
Wood is good in compression, although I suppose it depends what type of wood. I just assumed that hardwood is good in compression.
And yeah conductivity is good, steel wouldn't be useful as a power pole because it might go live.
PimpPyro
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Do you find that the papers get cruddier the furthur you go back?
Is it just me or does it seem that comparing 2004 to 2001, 2001 is quite a bit more difficult, and the questions are about context that seems to be dissimilar to what you have been studying?
Is it just me or does it seem that comparing 2004 to 2001, 2001 is quite a bit more difficult, and the questions are about context that seems to be dissimilar to what you have been studying?