Search results

  1. alcalder

    Generators generate anger :(

    This sounds like it is describing Back EMF. If the wire is moving to the left this will produce a conventional current down the wire. However, this now produces a back EMF to oppose the change that caused it. THUS, the conventional current down the wire in that magnetic field produces a force...
  2. alcalder

    building a motor

  3. alcalder

    Urgent Help Needed!!

    Wikipedia knows everything. There are even timelines and info on the development of all the different types of transport. Hope this is what you are looking for. http://en.wikipedia.org/wiki/History_of_transport
  4. alcalder

    Know Nothing at SDD

    Actually you probably know more than you think. So don't panic, work from there. http://en.wikipedia.org/wiki/Array An array is just like a list of values or list of a list of values. OK let's perhaps look at the dates of Sundays in a year. Let's call the array YearSundays. There are 52...
  5. alcalder

    Eddy Currents/Back EMF

    http://en.wikipedia.org/wiki/Eddy_current http://en.wikipedia.org/wiki/Back_emf Back emf pushes back against the current that produced it - Lenz's Law. Eddy currents are circulating flows of electrons within a conductor that produce a magnetic field that opposes the magnetic field that...
  6. alcalder

    contribution of development of space exploration

    Trying to get all those rockets to fire at the same time to get that thing into the air was a major problem. They had such rudimentary electronics and computers. It's a wonder we ever made it to the moon in the 1960's!!!!
  7. alcalder

    Consolidate my understanding..

    Think of a power source as a pump that is pumping the water (electrons) up a long hill. The hill is then the circuit. The electrons go from negative (the top of the hill) to the positive end (bottom of the hill) because of the nature of the source (pump). The fact that the electrons then get...
  8. alcalder

    Speed of light-anyone???

    I'm so sorry LingB. Just go with the basic theory that the HSC syllabus outlines and is in the textbooks. But always keep in mind it is just a theory and an early one at that. But then again, part of the Physics syllabus is to appreciate the development of theories over time. The classic one...
  9. alcalder

    Woah!!

    Old? Dear me! Then your teachers must be ancient. Even as you get older in years, you still don't feel old inside if you don't want to. And 18! Even 20! Gosh not even a pimple on life. ;) Enjoy youth.
  10. alcalder

    Smarties... (urgent!!)

    Perhaps you could go to your teacher and ask to do the prac during lunch time or recess. There is nothing like actually doing the prac for youself to get the info first hand. It also helps when remembering it for use in exam questions. OR, you could perhaps ask for an extension and a couple of...
  11. alcalder

    Health, Culture and Fitness

    Do you perhaps have some guiding questions in order to elicit information from people?
  12. alcalder

    medical phyiscs, who else is doing it?

    Remember, the options you do depend on the strengths of the teacher and what they did at Uni and feel comfy with. eg From Quanta to Quarks - likely to be a Chem/Physics major Astrophysics - Physics major in Astronomy Geophysics - Geology/Physics major Medical Physics - biology/physics major The...
  13. alcalder

    Consolidate my understanding..

    Conventional current is the direction of flow of positive particles. This was defined before they found out that current is actually the flow of negatively charged electrons. Thus conventional current is in the opposite direction to the flow of particles that causes it. SO, when using the...
  14. alcalder

    Speed of light-anyone???

    And if they prove it is not constant then the whole "freaking theory" goes out the window. Hence the reason that most scientists will not cause that apostasy and continue on regardless. It happens all the time. There is one guy challenging Newton's Laws and is getting howled down because he is...
  15. alcalder

    Speed of light-anyone???

    Is this true?? Very good question. Can they prove it? Here is a site that lists some experiments designed to test various aspects of Einstein's relativity. http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html But again, is the speed of light constant? A good question. Some...
  16. alcalder

    Physics HSC Study Guides & Textbooks

    Re: The best physics textbook This link at HSC Online lists all recommended textbooks for HSC and Prelim Physics: http://hsc.csu.edu.au/physics/teachers/2340/phys_teachers.htm I have used both Physics 1 & 2 Jacaranda books. They are very good at addressing the dot points but in some places...
  17. alcalder

    Atomic Weight Comparison

    http://en.wikipedia.org/wiki/Atomic_weight The relative isotopic mass is the relative mass of the isotope, scaled with carbon-12 as exactly 12. Before the 1960s, this was expressed so that the oxygen-16 isotope received the atomic weight 16, however, the proportions of oxygen-17 and oxygen-18...
  18. alcalder

    You *know* you're a physics nerd when...

    You donate your time to come to BOS and share information with other Physics nerds.
  19. alcalder

    HEELLPP infomation systems hw

    I am assuming this is for the dot point: [/B]Check out HSC Online: http://hsc.csu.edu.au/senior_science/core/info_systems/9_4_1/941net.html There are links there to how phones, radios, tv's and CD's work. TV circuit diagrams: http://cxema.ru/TV%20SETS.htm Phone circuit diagrams...
  20. alcalder

    Help! with Core-1.1

    Gravitational Potential Energy is the potential a body has to do work on its own in a gravitational field. But to increase the GPE YOU must do work in order to do this (conservation and conversion of energy from KE to GPE) eg lift a ball up off the ground, you have added some GPE and when you...
Top