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Algebra of Vectors

  • Thread starter Sam Cepeda
  • Start date
  • #1

Homework Statement

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Homework Equations





The Attempt at a Solution


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I am not sure if this is the correct way of finding the difference between two vectors. I thought that if "B" was negative then it's direction would change as well as it's angle. If the angle changes then are my calculations wrong (I used original angle)? I was also curious to know if a similar process applies when multiplying two vectors?

Thanks in advance
 

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  • #2
haruspex
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Your working is correct.
if "B" was negative then it's direction would change as well as it's angle
A change of angle is a change of direction, no?
You can think of ##-\vec B## as a force of "magnitude" -B in the direction of ##\vec B##, or as a force of magnitude B swung round through 180 degrees from ##\vec B##. But don't mix the two.
Okay, I know magnitudes are always non negative, hence the quotes.
 

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