Measuring position, velocity and acceleration in relative motion

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SUMMARY

The discussion focuses on measuring position, velocity, and acceleration in relative motion, specifically in the context of uniform circular motion. The vector representation of position in frame A is identified as ##r(t) = (0; y)##, indicating its tangential nature. Velocity from frame B is confirmed to be ##\omega##, while acceleration requires consideration of three dimensions, expressed in terms of initial velocity (v0) and time (t). The relationship between the rotating axes in frame A is also clarified, emphasizing the distinction between z' and the rotating x' and y' axes.

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  • Understanding of uniform circular motion
  • Familiarity with vector representation in physics
  • Knowledge of relative motion concepts
  • Basic grasp of rotational dynamics
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  • Study the mathematical representation of uniform circular motion
  • Learn about vector calculus in three dimensions
  • Explore the principles of rotational dynamics in physics
  • Investigate the effects of initial velocity on motion trajectories
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Physics students, educators, and professionals in engineering or mechanics who are interested in understanding the dynamics of relative motion and circular trajectories.

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Homework Statement
A particle moves with constant velocity ##v_0## in the ##y## direction with respect to an inertial system ##A(x;y;z)## as depicted in the picture. There is another system ##B(x';y';z')##, which is not inertial and rotates with constant angular velocity ##\omega##.
Determine
a) ##r(t)## from the perspective of ##B## and ##A##
b) the velocity measured from ##B##, i.e., the velocity relative to ##B##
c) the acceleration measured from ##B##, i.e., the acceleration relative to ##B##
Relevant Equations
##\vec a=\vec a_B + \vec{\dot \omega} \times \vec r + \vec \omega \times (\vec \omega \times \vec r) + 2. (\vec \omega \times \vec v_{rel}) + \vec a_{rel}##
Well, ##r(t)## in ##A## is just a vector ##(0;y)## because is tangent to the trajectory. Then, from the perspective of ##B## the particle moves in an uniform circular motion. Is this right?

The velocity from ##B## must be ##\omega##, right?

And what about acceleration?
 

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Like Tony Stark said:
Well, r(t) in A is just a vector (0;y)
You need three dimensions, and it should be expressed in terms of v0 and t.
Like Tony Stark said:
from the perspective of B the particle moves in an uniform circular motion
No. That would be true if v0=0.
If I read the diagram correctly, z'=z while the x' and y' axes rotate in A's xy plane.
 

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