Proving Vector A and d\vec{}A/dt Are Perpendicular With Constant Magnitude

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please help me(a vector problem)

Homework Statement



i m very confuse about this assignment. please help me how to prove.

If \vec{}A has constant magnitude show that \vec{}A and d\vec{}A/dt are perpendicular provided that d\vec{}A/dt \neq0

also give one physical example of this problem.

please help me in this problem.

thnx.


Homework Equations





The Attempt at a Solution

 
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This can be thought of as a circular motion problem with constant radius. Since the radius vector has a constant magnitude (constant radius), then only the position of the vector changes with time. Draw two vectors with magnitue A, one displaced an amount delta theta from the other. Find the vector difference which will be delta A, then take the limit of delta A divided by delta theta as delta theta goes to zero.
 


i didnt got u !

Hey Chris buddy can u pleasez solve it for me pleasez..

thnx in advance.
 


jawwadaziz said:
i didnt got u !

Hey Chris buddy can u pleasez solve it for me pleasez..

thnx in advance.

No, we will not solve this for you. You have been given a great hint, and now the rest is up to you.

Please re-read the Rules link at the top of the page, especially the part about how you must do the bulk of the work on homework/coursework problems.

Show your work, and if you have a specific question, we can offer hints and tutorial help. We do not do your homework for you.
 


ooops sorry !

I didnt knew the rules..
it won't happen next tym.
 


The magnitude of A squared is A.A (dot product). Is that a help?
 
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