12.2.2—Centripetal acceleration causes circular motion with a constant angular

In uniform circular motion, acceleration is centripetal, directed toward the centre, with magnitude a=v²/r=rω².

The velocity is tangential while acceleration is radial; the inward resultant force is F=mv²/r.

Doubling speed at fixed radius quadruples centripetal acceleration, while doubling radius halves it for fixed speed.

“Centripetal force” is not a new force type—it is the name for the inward resultant supplied by tension, gravity, friction or another interaction.