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ahmeeeeeeeeeed

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Everything posted by ahmeeeeeeeeeed

  1. Hello Have dinosaurs existed with men ??? Is there any scientific evidence ??? and , someone told me that using the Radiocarbon isn't beneficial and is not accurate while talking about dinosaurs >> and please see this video about the co-existence >> Thanks
  2. Ok may be not so real >> but I mean a transformer where the P(out) Is less than P (in) like http://www.scribd.com/doc/31506096/Transformer
  3. HELLO In a real transformer , Why Ns Is= Np Ip ??? Please explain simply
  4. Hello What is the relation between the resistance and lost Thermal energy in a circuit ? I mean >> If we put a ((big)) resistance .. the Intensity of the current will lessen If we are trying to lessen the lost energy (it is lost as heat) >> what should we do ?? use a material that has low Resistivity ? or high Resistivity ?? the first will make the intensity of the current increase >> and that it self affects the lost energy as heat and related to this in "coldeg's X-ray tube" why do we use copper (attached to the target of the Wolfram) ?? Thanks
  5. Hello I want to ask.. When there is a circuit ( battery - Rheostat -lamb) When we decrease the Rheostat .. the current will increase But momently there will be a self induced current which will weaken the current I want to know >> momently , which one will beat the other ?? And why ? And If we increase the Rheostat , the current will decrease .. but there will be a self induced current which will strengthen it >> which will beat ?? AND why ??
  6. so the reading will be less in both cases ? And another thing please >> when you say a diamagnetic material >> isnot copper and gold diamagnetic ?? when does this repulsion occur ?? If there was a current passing through the material ?? And as for my first question .. there is no current in the wrought Iron .. Thanks in advance
  7. But in both ways the reading of the balance would be less than its reading when there was no magnatic field ?? I mean Is it sure that both north pole and south pole will attract the wrought Iron ?? because in one case >> the field direction would be down towards the Iron but in the other case the field goes up not down>> Wouldn't the first make the Iron heavier ? and the reading will be more ??
  8. Or I think it would be more accurate to say : the effect of the magnetic field direction .. going to the balance or away from it
  9. Well, I just study this in simple Doesn't moving a cylinder in a magnetic field that doesn't change Equal putting a still cylinder in a magnetic field that changes due to the change in the current in the coil ?? (sorry If the statement is not clear ) It is written that when we put the cylinder there is eddy currents (the cylinder doesn't move , put the Intensity of the magnetic field changes) But then it is written that one way to decrease it is to make the cylinder into thin bars and put it paralleling the axis so I want to know >> the decrease in the eddy current here is just due to (cutting) the cylinder into thin bars , not to putting it paralleling the axis , As it was already paralleling the axis when it was a cylinder , Am I right ?? If I am not right , what is the difference ?
  10. Hello If we have a coil >> and then moved a Cylinder of wrought Iron in it >>we now that the magnetic field inside this coil will parallel the axis And so the Angle between the magnetic field and the movement direction would be Zero (wouldn't it? ) Would there be a current in the cylinder ?? I mean Eddy current Thanks in advance
  11. Hello Do Lines of magnetic flux have weight ?? I have this question this photo I drew it there is a Circuit with a coil >> there is a sensitive balance with a ball of wrought Iron The question is What will happen to the balance's reading when the current is in the direction in the picture ?? And what will happen If we made the current in the opposing direction ?? Thanks in advance
  12. Hello, has the iron we mine now come from meteorites ??
  13. hello I was reading this book The earth , its birth and growth but it is on google books and not complete it talked about theories of earth's core http://books.google.com/books?id=Bw84AAAAIAAJ&pg=PA28&dq=how+was+the+core+of+the+earth+formed+%3F&hl=en&ei=Mn89TKmIIYWd4Qa7mc3GAg&sa=X&oi=book_result&ct=result&resnum=7&ved=0CEIQ6AEwBg#v=onepage&q=how%20was%20the%20core%20of%20the%20earth%20formed%20%3F&f=false from page 28 to 31 and then 32 and 33 are not there I want to know is the idea that "the components of earths core were molten and then iron and heavy metals went to the centre and the lighter objects went above" correct or was it refused now ?? and please could you explain what is written here answering the question page 22 ? http://books.google.com/books?id=DKJLuS2pEywC&pg=PT33&dq=how+was+the+earth%27s+core+formed+%3F&hl=en&ei=65o9TJeEK5qU4gbV97GTBw&sa=X&oi=book_result&ct=result&resnum=5&ved=0CDwQ6AEwBA#v=onepage&q=how%20was%20the%20earth%27s%20core%20formed%20%3F&f=false Thanks and sorry for disturbance .
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