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Applications of calculus to the physical World Q (1 Viewer)

cutemouse

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Ek=(1/2)*mv2 (Kinetic Energy) -- Tell me how that can be negative, and don't say that mass can be negative either!

Work done can be negative, but you need to define positive (ie. if work is done for you, or if you do work).

With voltage it's a different thing they use imaginary numbers due to conventional current (IIRC).

lolokay said:
can't scalars be considered negative? eg. energy, voltage? you can subtract scalars.. (in this question displacement and distance are interchangeable anyway)
 

lolokay

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nah, the mass isn't negative - that's just absurd. the velocity is imaginary :p

you need a reference frame - define positive/negative - for giving vectors a direction too, don't you? when summing voltage drops and rises around a loop in a circuit you take one to be positive and one to be negative, a decrease in energy is a negative energy change etc.
 

narima

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right so im new to BOS, whats trolling lol and how do i post a question? :S
thanks
 

cutemouse

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To post a question -- Go anywhere in this website, then press CTRL+W... A 'post question' box should pop up. If it doesn't and something expected happens then just reopen the internet browser and try it for the next 9 times. If the problem persists then reply here and tell us the problem.
 
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