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Physics/Centripetal Acceleration



In constant circular motion,
Centripetal Acceleration(a)=r(radius)*alpha(angular acceleration)
Centripetal Acceleration is directed along r towards the centre. What is the direction of alpha? Tq

Not quite.  Your first equation relates to the acceleration of something at radius r, like the road under a car when its wheels are turning at angular acceleration alpha.  It relates the linear motion of the edge of a pulley/wheel/circular object to the angular acceleration around.  It is not centripetal, that is different, and equal to r*omega^2, where omega is the angular velocity of the wheel.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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