• Many people believe that if an object is accelerating then its speed must be changing. This is not true. Speed is merely the magnitude of a vector. The direction of a vector can change without changing its magnitude. This means I can change my velocity, i.e. accelerate, but I don't have to change my speed.
  • Warning: careful consideration must be made when ever using the term centripetal force, as it implies an actual force, separate from others, in the radial direction. The term centripetal is referring the net effect of all the real forces when an object is in UCM. In the case of UCM the net force is in the radial direction and that net force (from real forces) is called the centripetal force.
  • The difference between Centripetal and Centrifugal
  • Another issue people have is that they believe that since, in uniform circular motion, the speed of the object stays constant then the object must be in equilibrium. They then assume that another force is balancing out the inward forces. This is not true. For an object to change its direction, it must have a non-zero net force.