Finding the Displacement Vector from 3 Given Vectors

AI Thread Summary
To find the displacement vector from multiple given vectors, it's essential to calculate the distance for each vector and sum them. When dealing with more than two vectors, it's recommended to either add them two at a time or break them down into their components before summing. The parallelogram method is only applicable for adding two vectors directly. After applying this approach, the user successfully solved the problem without needing additional help from the teacher. Understanding vector addition and component breakdown is crucial for accurately determining displacement in physics.
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My physics teacher has given me a worksheet with several problems involving trigonometry to find a displacement vector from a set of given vectors. Since this is my first year in physics, I feel out of my element and would really appreciate any help or direction given to me on how to go about this problem. It is as follows:

"A car travels at 65 km/hr for 30 minutes SSW, then 38 km/hr for 45 minutes SW, then 50 km/kr for 25 minutes due W. What is the car's displacement? What is your total distance?"I am aware that in order to find the total displacement, you must calculate the distance traveled for each vector and then add them together. I have done that, already.

I have attempted to put the vectors together "tip-to-tail", but since the tips of the vectors face west, I have sketched a shape where a "parallelogram" is not formed. My physics teacher only showed brief examples of problems where the three vectors can be connected by a displacement vector to form a figure similar to that of a parallelogram. (i.e. you travel 117 km ENE, then 95 km SE, then 298 km SSW. What is your displacement & total distance?)

Maybe I am just setting the problem up wrong? I've been working on manipulating the vectors to make said shape, but I feel as if that would just alter the displacement from the origin and not give me the correct answer.

I am not sure where to go from here, and would really appreciate the help since I'm not getting the information needed in class. I accept full responsibility for my confusion, however. Perhaps I'm just over-thinking this "simple" problem?

Thank you in advance. :redface:
 
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The parallelogram applies when you are adding two vectors. If you are adding more than two, either deal with them two at a time (add two and get a resultant, then add the next vector to that resultant, and so on), or, break all the given vectors down into their individual components at the start and sum the like-components all at once. Combine the resulting component sums into a final resultant vector.
 
gneill said:
The parallelogram applies when you are adding two vectors. If you are adding more than two, either deal with them two at a time (add two and get a resultant, then add the next vector to that resultant, and so on), or, break all the given vectors down into their individual components at the start and sum the like-components all at once. Combine the resulting component sums into a final resultant vector.

I tried this, then asked my physics teacher for some extra help and I ended up not needing it since I got the right answers. Thank you very much for your time, it's really appreciated!
 
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