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HSC Physics Marathon 2013-2015 Archive (2 Viewers)
- Thread starter Magical Kebab
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re: HSC Physics Marathon Archive
Magnetic fields are excluded from the superconductor, forcing the magnet to be repelled from the superconductor thus causing it to rise up (meisner effect).
Quantum pinning ---> stops the magnet moving horizontally off the superconductor.
idk this is what i learnt from the STUDENTS GUIDE TO HSC PHYSICS....so ill go check a textbook to make sure.
Two reasons:
Magnetic fields are excluded from the superconductor, forcing the magnet to be repelled from the superconductor thus causing it to rise up (meisner effect).
Quantum pinning ---> stops the magnet moving horizontally off the superconductor.
idk this is what i learnt from the STUDENTS GUIDE TO HSC PHYSICS....so ill go check a textbook to make sure.
re: HSC Physics Marathon Archive
The superconductor is able to exclude the external magnetic field, and when this external magnetic field is placed near the superconductor, eddy currents will be induced in the superconductor and flow in a way to oppose the external magnetic field, creating a repulsive force. When the weight force of the magnet is balanced by the repulsive force created by the flow of eddy currrents, the magnet will levitate. Someone correct me if im wrong I just wrote that off the top of my head and I'm gonna revise this stuff tomorrow or tonight
What's quantum pinning o-o
The superconductor is able to exclude the external magnetic field, and when this external magnetic field is placed near the superconductor, eddy currents will be induced in the superconductor and flow in a way to oppose the external magnetic field, creating a repulsive force. When the weight force of the magnet is balanced by the repulsive force created by the flow of eddy currrents, the magnet will levitate. Someone correct me if im wrong I just wrote that off the top of my head and I'm gonna revise this stuff tomorrow or tonight
keepLooking
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re: HSC Physics Marathon Archive
Apparently not. According to the other thread, it is solely based on the Meissner effect based on the syllabus because if you conduct an experiment and place a magnet above a superconductor before it reaches critical temperature, it will still levitate when cooled. There is no change in magnetic flux that induces any surface eddy currents.
re: HSC Physics Marathon Archive
From the student's guide:
The Meisnner effect is separate to the induction of eddy currents which would theoretically perfectly oppose the magnetic field of a magnet. This is shown true because if a magnet is placed on a superconductor as it is being cooled, it will jump in the air the superconductor becomes superconducting --> this shows it is not an induction phenomenon as a change in magnetic flux is required to induce eddy currents. Therefore levitation occurs due to the exclusion of magnetic fields from the superconductor
From the student's guide:
The Meisnner effect is separate to the induction of eddy currents which would theoretically perfectly oppose the magnetic field of a magnet. This is shown true because if a magnet is placed on a superconductor as it is being cooled, it will jump in the air the superconductor becomes superconducting --> this shows it is not an induction phenomenon as a change in magnetic flux is required to induce eddy currents. Therefore levitation occurs due to the exclusion of magnetic fields from the superconductor
re: HSC Physics Marathon Archive
anyone wanna take a bite at this?? I don't really know what to mention for full marks.
TQuadded
Breaking the limits.
re: HSC Physics Marathon Archive
Effects on Society:
- Since voltage & current could be increased & decreased, power could be efficiently transported over large
distances
- Allowed power stations to be located away from suburban areas and closer to resources needed to generate
them (coal and hydro etc.) which helped to bring down its price
- AC power generation could be carried out on large scales and then distributed over long distances to many
people efficiently
- Economies of scale could be achieved, resulting in dramatically cheaper electricity
- Not only the rich could afford power
- Development of longer working hours as a result of widespread lighting etc.
- Affordability resulted in the mechanisation of many industrial processes, which effectively reduced long
term demand for labour, resulting in reduction in unskilled jobs and increase in unemployment
- Increased productivity – economic growth
- Shift from blue collar work to a majority of white collar work
- Raised living standards as affordability and accessibility were greatly increased
- Energy available to most rural communities
- Dependency on power resulted in essential services being forced to develop ‘back up’ electrical sources
o A disruption of supply compromises safety and could result in large scale production decreases
Environmental Impacts:
- Power stations could be located away from cities and suburbia which reduced short term effects of air
pollution
- The construction of power lines resulted in natural habitat being destroyed
- Growing dependency of power resulted in rapid resource use resulting in depletion of non-renewable
resources
- Fossil fuel power stations have environmental effects such as thermal pollution, acid rain & air pollution
due to release of particles & oxides of nitrogen & sulfur
- Huge amounts of CO2 released by power stations contribute to enhanced greenhouse effect thought to be
raising Earth’s temperature
Effects on Society:
- Since voltage & current could be increased & decreased, power could be efficiently transported over large
distances
- Allowed power stations to be located away from suburban areas and closer to resources needed to generate
them (coal and hydro etc.) which helped to bring down its price
- AC power generation could be carried out on large scales and then distributed over long distances to many
people efficiently
- Economies of scale could be achieved, resulting in dramatically cheaper electricity
- Not only the rich could afford power
- Development of longer working hours as a result of widespread lighting etc.
- Affordability resulted in the mechanisation of many industrial processes, which effectively reduced long
term demand for labour, resulting in reduction in unskilled jobs and increase in unemployment
- Increased productivity – economic growth
- Shift from blue collar work to a majority of white collar work
- Raised living standards as affordability and accessibility were greatly increased
- Energy available to most rural communities
- Dependency on power resulted in essential services being forced to develop ‘back up’ electrical sources
o A disruption of supply compromises safety and could result in large scale production decreases
Environmental Impacts:
- Power stations could be located away from cities and suburbia which reduced short term effects of air
pollution
- The construction of power lines resulted in natural habitat being destroyed
- Growing dependency of power resulted in rapid resource use resulting in depletion of non-renewable
resources
- Fossil fuel power stations have environmental effects such as thermal pollution, acid rain & air pollution
due to release of particles & oxides of nitrogen & sulfur
- Huge amounts of CO2 released by power stations contribute to enhanced greenhouse effect thought to be
raising Earth’s temperature
nerdasdasd
Dont.msg.me.about.english
re: HSC Physics Marathon Archive
I'm not sure if you guys have seen this in my sig ... the ultimate physics knowledge tests
PHYSICS MC and ANSWERS >> http://sdrv.ms/H3da9C
120 questions (multiple choice + short Questions ) ... with band 6 solutions too!
PHYSICS CORE OPTIONS MC HARD TEST (with solutions)>> http://sdrv.ms/GXNTOQ
>>> 50+ MC for every core physics subject
I'm not sure if you guys have seen this in my sig ... the ultimate physics knowledge tests
PHYSICS MC and ANSWERS >> http://sdrv.ms/H3da9C
120 questions (multiple choice + short Questions ) ... with band 6 solutions too!
PHYSICS CORE OPTIONS MC HARD TEST (with solutions)>> http://sdrv.ms/GXNTOQ
>>> 50+ MC for every core physics subject
Kaido
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re: HSC Physics Marathon Archive
Society:
- Widespread distribution of electricity through the production of AC -> talk about transformation + effectiveness of AC (powerloss etc.) -> maximising efficiency as less energy loss = lower cost etc
- The electricity generated leads to imporved living/leisure activities for people + job opportunities in new technological sectors
- Improved connecteedness betn ppl, talk about phones etc.
- Drawback would be job redundancy
Environment:
- Adv of being able to be located far away (as opposed to DC generators)
- Pollution due to burning of fuels etc -> illness
- Extremely high demand -> increased consumption and thus depletion of fossil fuels
- Removal of large lands to create power stations for AC generation
- (Aestheticallydispleasing)
Summary statement...
Alright, atargainz one step ahead of me :/
I'll list the main points:
Society:
- Widespread distribution of electricity through the production of AC -> talk about transformation + effectiveness of AC (powerloss etc.) -> maximising efficiency as less energy loss = lower cost etc
- The electricity generated leads to imporved living/leisure activities for people + job opportunities in new technological sectors
- Improved connecteedness betn ppl, talk about phones etc.
- Drawback would be job redundancy
Environment:
- Adv of being able to be located far away (as opposed to DC generators)
- Pollution due to burning of fuels etc -> illness
- Extremely high demand -> increased consumption and thus depletion of fossil fuels
- Removal of large lands to create power stations for AC generation
- (Aestheticallydispleasing)
Summary statement...
Alright, atargainz one step ahead of me :/
Last edited:
TQuadded
Breaking the limits.
re: HSC Physics Marathon Archive
Daaayuuum. That makes the marker wet and give you 10 marks instead.
godofindolence
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re: HSC Physics Marathon Archive
Everytime I write about this, it turns into an economics essay :/
re: HSC Physics Marathon Archive
You can transmit DC through AC transmission lines can't you???
Dont like this question because there is not really much difference between AC and DC transmission lines (--> AC lines is coated more to prevent leakage of EMR)
You can transmit DC through AC transmission lines can't you???
Drsoccerball
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re: HSC Physics Marathon Archive
lel because maybe AC is the only one you can use in the power lines?
TQuadded
Breaking the limits.
re: HSC Physics Marathon Archive
AC Advantages:
- Easier voltage to be stepped-up and down.
- Allows high-voltage transmissions.
- Less power loss.
DC Disadvantages:
- Much harder to be stepped-up and down.
- High power loss.
- Much more fatal discharge.
(Put 'em in a paragraph.)
I guess just advantages of AC?
AC Advantages:
- Easier voltage to be stepped-up and down.
- Allows high-voltage transmissions.
- Less power loss.
DC Disadvantages:
- Much harder to be stepped-up and down.
- High power loss.
- Much more fatal discharge.
(Put 'em in a paragraph.)
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