Position Vectors: Get Help & Understand Concepts

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    Position Vectors
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The discussion centers on understanding position vectors and their visualization in relation to polar and rectangular coordinates. Participants express difficulty in grasping the concept, particularly regarding the angles between vectors and axes. Clarifications are made about the correct interpretation of angles, emphasizing that theta should be considered between the r vector and the x-axis, not the z-axis. Recommendations for further reading include Spiegel's work on vectors and curvilinear coordinates to aid comprehension. Overall, the conversation highlights the challenges of visualizing vector transformations and the need for accurate conceptual understanding.
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Homework Statement


upload_2015-12-9_18-29-34.png


Homework Equations


Relevant equations can be derived from the formulas, by exchanging x to v, v to a, etc.

The Attempt at a Solution


I've tried to graph them, but I am not able to visualize or understand them.

Please help me about these questions, I need some hints.

If you can suggest me some parts or questions relevant to this topic, I will be so happy because I cannot understand this concept.
 
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Hi,

the info given in qn is not correct. here angle theta cannot be between r and z axis. as in that case theta becomes 90 degree and that doesn't make sense. theta is between r vector and x-axis and in that case it is just a transformation between rectangular and polar coordinates in 2-D. Please check attachment for your help. I guess you can try qn. c and qn. d now
.
UNW4Db049XQFCPf6TAy2g9H8.jpg
 
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Hello,
I was looking for it also, thank you for your kind reply and your work, I am trying to visualize the angle for the z axis, since there is no component for the z hat plane, it doesn't make sense thus it is 90 degrees. I agree with you, neverthless I told them this morning, but he told that there is more to think about that point. Thank you for your help, I understood your kind help correctly. Do you have any books in your mind, about the part of this classical mechanics?
 
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But if we neglect that z part and exchange with x hat, it is reasonable. Thank you anyway kind friend, I will be solving it as x
 
Hi,

See if the angle is between Z axis and r vector than definitely r hat becomes y hat and theta hat becomes (-ve) x hat. from that perspective it is a rotation of the vector by 90 deg if you transform from rectangular to the r-theta co-ordinate.

You can follow Spiegel for concepts on Vectors and Curvilinear co ordinates.
 
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