Glossary

Angular velocity - angular displacement divided by elapsed time during which the displacement occurs.

Banked curve - a curve that is tilted above the horizontal at some angle.

Centripetal acceleration - "center-seeking" acceleration for an object moving in a circular path (a vector quantity).

Centripetal force - the net force required to keep an object of a known mass moving at a speed on a circular path of a certain radius. It always points toward the center of the circle.

Coefficient of friction - unitless number that is a ratio of the frictional force divided by the normal force.

Frictional force - force that acts between two surfaces that are moving past one another or when there is no relative motion.

Linear velocity - velocity along a line.

Net force - sum of the forces acting on an object.

Normal force - perpendicular force that a surface exerts on an object with which it is in contact.

Static friction - frictional force that acts when there is no relative motion between the surfaces of two objects.

Unbanked curve - a curve that is not tilted above the horizontal.

Uniform circular motion - motion of an object traveling at a constant (uniform) speed on a circular path.