College Physics

# Glossary

center of gravity
the point where the total weight of the body is assumed to be concentrated
dynamic equilibrium
a state of equilibrium in which the net external force and torque on a system moving with constant velocity are zero
the ratio of output to input forces for any simple machine
neutral equilibrium
a state of equilibrium that is independent of a system’s displacements from its original position
perpendicular lever arm
the shortest distance from the pivot point to the line along which $FF$ lies
SI units of torque
newton times meters, usually written as N·m
stable equilibrium
a system, when displaced, experiences a net force or torque in a direction opposite to the direction of the displacement
static equilibrium
a state of equilibrium in which the net external force and torque acting on a system is zero
static equilibrium
equilibrium in which the acceleration of the system is zero and accelerated rotation does not occur
torque
turning or twisting effectiveness of a force
unstable equilibrium
a system, when displaced, experiences a net force or torque in the same direction as the displacement from equilibrium