Unit Vectors Homework: Write Vector Expression for Golf Ball Position

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The discussion focuses on deriving a vector expression for the position of a golf ball hit off a cliff, with given x and y coordinates as functions of time. The correct vector expression is identified as (16.0t) i + [(3.30t) - (4.90t^2)] j, incorporating both components appropriately. A participant initially struggles with understanding how to combine the x and y components into the vector format but later realizes their mistake and clarifies their understanding. The conversation emphasizes the importance of correctly identifying the components associated with the unit vectors i and j. Overall, the thread illustrates the process of solving a physics problem involving vectors and the learning experience that comes with it.
Jbright1406
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Homework Statement


A golf ball is hit off a tee at the edge of a cliff. Its x and y coordinates as functions of time are given by the following expressions.
x = (16.0 m/s)t
y = (3.30 m/s)t - (4.90 m/s2)t^2

Write a vector expression for the ball's position as a function of time, using the unit vectors i and j. (Use t, i and j as necessary.)


Homework Equations





The Attempt at a Solution


The best i am coming up with is
(19.30 m/s)t i - (4.90 m/s^2)t^2 j

I know I am missing something about the conversion but i don't know what, and am really confused about vectors


EDIT: I realized what i did. I get really confused with the vectors. i didnt realize the two x was going to compose the i component and the y was going to compose the j component. Thank for the help, but TBH I am glad a figured it out on my own...im sure ill remmeber now! Thanks
THe answer i got was
(16.0t) i + [(3.30t)-(4.9t^2)] j
 
Last edited:
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Why did you just drop the (3.30 m/s)t part from the j component?

Writing a position vector with i,j (and sometimes) k is just writing everything in the same equation, basically, with an i after the x component, a j after the y, and a k after the z. This is what it boils down to, there's a bit more to it than that and if you have any specific questions I could try to help with that.
 
I didnt just drop the 3.3 i added it to the 16.0; i realized where i was mistaken at. check out the edit i just posted after you answered! Thank you for your help though! :-)
 
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