Displacement Vectors: Understand x, y, z & i, j, k

AI Thread Summary
Displacement vectors are represented using the equation r=xi+yj+zk, where x, y, and z denote the magnitudes of the vector components in their respective directions. The unit vectors i, j, and k correspond to the x, y, and z axes, respectively, and are essential for clearly defining vector directions. Understanding this distinction helps avoid confusion between the magnitude and direction of vectors. For example, the vector 5i + 5j indicates a magnitude of 5 units in both the x and y directions. Clarifying the use of these notations is crucial for mastering vector concepts in a fast-paced class.
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Homework Statement


DISPLACEMENT VECTORS



Homework Equations


r=xi+yj+zk=<x,y,z>



The Attempt at a Solution


For all of the problems I am starting to do class we must use the equation above.
I do not understand why we use i,j,k and how they are similar to x,y,z and how to use them.
Please help! I was absent the day we learned this and it is a fast pace class and I am trying to understand this but can't seem to fully do so!
 
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Its sort of the same thing, but not quite: i, j, and k are unit vectors in the x ,y, and z directions. Using x, y,and z subscripts, often imply magnitudes of the component vectors in those directions. So a vector 5i + 5j has a magnitiude of 5 units in the x direction and 5 units in the y direction. If you call the vector 5x + 5y, its easy to confuse yourself, as in your other post. So don't.
 
thankyou!
 
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