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Worded definition of momentum

  1. Jan 2, 2014 #1
    I know Newton described it as 'the quantity of motion' but are there any other more descriptive or better definitions?
    Thanks in advance!
  2. jcsd
  3. Jan 2, 2014 #2

    Simon Bridge

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    In what way "better" or "more descriptive" ... it is the amount of motion something has.
    After that you have to say how it is related to something else (product of mass and velocity) - or justify the terminology like: why is "speed" not the amount of motion?

    Have you canvassed the different definitions online?
  4. Jan 2, 2014 #3
    Thanks very much for your reply, in my Physics lesson I was told by my tutor not to use "quantity of motion" as a definition for momentum and I don't really see why, yes I've come across a few such as "mass in motion" and "the impetus of a body resulting from its motion" and wondered what was the most suitable, or whether they are all equally suitable. Thanks
  5. Jan 2, 2014 #4


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    How about "the conserved quantity which is associated with the invariance of the laws of physics under spatial translations?" :tongue2:

    (which may or may not be above the level that you're studying at... whatever level that is... :wink:)
  6. Jan 2, 2014 #5
    Hi jtbell, thank you for your reply but that looks way above the level that I'm studying at, I'm studying second year of A level, which is like the year before you can start your undergraduate degree in England.
  7. Jan 2, 2014 #6

    Simon Bridge

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    What is the context of the question?

    Could it be that they want to see how you understand momentum rather than just regurgitate a standard definition? In which case - what do you think momentum is? In your own words.
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