Acceleration is not in direction of force

Meir Achuz
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"acceleration is not in direction of force"

The following quote was in a post now closed:
"i don't know how this person says that acceleration is not in direction of force
there fore angle HAS to be zero degrees."
If "force" is meant to be dp/dt, then "acceleration is not in direction of force."
Since dp/dt=m\gamma^3[a+vX(vXa)], there are important cases where
"acceleration is not in direction of force."
 
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Meir, when a thread has been locked, it defeats the purpose of locking it, if a new thread starts off on attempting to dispute something that was said in the earlier thread. A continuation of the discussion is specifically what the moderating mentors wanted to avoid.
 
Err..Sorry it was me who typed that.I meant to say isn't acceleration in the direction of motion.Sorry my mistake
 

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Thread 'Dirac's integral for the energy-momentum of the gravitational field'

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