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Concept in physics

  1. Dec 11, 2012 #1
    hi everyone i'm in my first year of electronic engineering and i have some questions which the professor of physics gave us but more as research than homeworks and to be honest i really tried but i didn't found anythings so i'm here to asking for your help
    1- what is the difference between: (A and B are vectors)
    the addition of A and B
    the sum of A and B
    2-is it true that in physics we have only scalars and vectors as quantities ?
    3-is it true that all quantities which have direction and magnitude are vectors ?
    4-what is the difference between the displacement and the path ?
    5-how using the significants figures contributed in the scientific development ?
    6- if you have the time and space can you find all other variables in physics ?
    7-acceleration has no scientific meaning , why ?
    8-the body of human is an accelerometer ,why ?
    9-the body of human is not a speedometer ,why ?
    if you can give me the answers or just tell me where i can found them it will really help me
    Last edited: Dec 11, 2012
  2. jcsd
  3. Dec 11, 2012 #2


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    Staff: Mentor

    In the version of American English that I use, they all mean the same thing. In the version of English used in your part of the world (wherever that is), perhaps there is a difference.
  4. Dec 11, 2012 #3
    that is what i said to the professor but he insist and told me that there is a difference :confused:
  5. Dec 11, 2012 #4
    Here is how you could respond to your professor:

    Of course there is a difference between A+B and "the sum of A and B". The difference happens to be zero.
  6. Dec 11, 2012 #5
    believe me i will :approve: but for the rest any suggestions
  7. Dec 11, 2012 #6


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    2017 Award

    Staff: Mentor


    That question is bad. In mathematics, you can express everything as vector. It does not matter if it is meaningful.

    I would say that a path has a specific way to "make" that displacement, but that depends on the precise interpretation of the question.

    The concept of significant figures can be nice to get a rough estimate of an uncertainty, but it is not used for serious scientific work.

    What does that even mean?

    Of course it has.

    Can you feel an acceleration?

    Speed relative to what? See principle of relativity.
  8. Dec 12, 2012 #7
    I think the clue to the (A & B) versus (A + B) is to be found in your course subject as an electronic engineer.

    You should look up
    AND gates
    OR gates
    XOR gates

    and you will have your answer
  9. Dec 12, 2012 #8
    tanks evryone
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