What does a physicist mean by "external" force? An external force is one caused by something outside of the body under consideration. An external force is one that acts at a distance where no contact is required. An external force is one that can affect the velocity of a body but not it's total energy. An external force is one that does not affect the body.

A physicist refers to an "external force" as a force that is exerted on an object from outside of the object itself. This force is caused by something outside of the body under consideration. An external force acts at a distance, meaning that no physical contact is required between the force and the object it is acting upon. An external force can affect the velocity of a body, which means it can change the speed or direction of the object. However, it does not affect the total energy of the body. This is because the total energy of a system is conserved, and an external force can only change the kinetic energy of the object, not its total energy. In summary, an external force is a force that originates from outside the object, acts at a distance, can change the velocity of the object, but does not affect its total energy.