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I want to be a physicist, but

  1. May 15, 2012 #1
    Ok, I've known for awhile now, that I want to be a physicist however, since I've started reading online materials at a higher level, my grades have been suffering. I'm wondering if I've begun to over think things. For example studying heat we were told to "Ignore" some heat transfers taking place. Am I overthinking? And is there anyway I can continue to study higher level phyics and still get high grades?

    For reference, I am excelling in chemistry and biology and studying GCSE triple science and Astronomy.

    Also is there any material I should read prior to the start of GCSE Astronomy, to help me get high grades.
  2. jcsd
  3. May 15, 2012 #2


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    One of, if not the most, important skills in physics is knowing when to make approximations and how correct they are. In my opinion it's not really taught well in the curriculum, but knowing when certain effects can be ignored and when they cannot is extremely important. You might have to take some of this on faith, but otherwise do try to convince yourself that what you're ignoring indeed is insignificant compared to other effects in the problem.
  4. May 15, 2012 #3
    I used to question these assumptions too. This last semester, I took a course on engineering thermodynamics. When constructing energy balance equations, we were often told to ignore effects from kinetic energy in favor of changes in enthalpy, heat, and work.

    Then one day the prof threw a curve ball and told us to calculate a change in energy including effects from kinetic energy. Want to know what changed? About a dozen joules - in a system where the kinetic energy changed by multiple kilojoules. If you ever question these assumptions, then do a side project and see just how accurate the assumption is. Usually the assumptions are pretty safe.
  5. May 15, 2012 #4
    I don't think you're over thinking, it sounds, like with many students, you're 'over thinking' improperly. It's necessary to think about why assumptions are necessary, good and physical.
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