Circular Motion Terms

Non-Uniform Circular Motion

Circular motion that involves a change in speed during a time interval

Centripetal Acceleration Symbol: ac Unit: m/s^2

component of the acceleration that changes the direction of the velocity - directed to center of circle

Tangential Velocity Symbol: v(t) Unit: m/s

linear speed of an object moving along a circular path

Tangential Acceleration Symbol: aT Unit: m/s^2

measuring if the tangential velocity is speeding up or slowing down

Speed Symbol: v Unit: m/s

the distance an object travels with respect to time (scalar quantity)

Net Force Symbol: ΣF Unit: Newtons (N)

the force needed to hold an object in a circular path Other name: Centripetal force

Uniform Circular Motion

the movement of an object at a constant speed around a circle with a fixed radius - not constant velocity

Frequency Symbol: f Unit: Hertz (Hz or 1/s)

the number of revolutions per second other name: cycles per second

Angular acceleration Symbol: a (alpha) Unit: rad/s^2

the rate of change of the angular velocity

Period Symbol: T Unit: seconds (s)

the time it takes for one complete revolution

Angular velocity Symbol: W (omega) Unit: rad/s

The angular displacement of an object divided by the change in time

Centripetal Force Symbol: Fc Unit: Newtons (N)

a force that acts on a body moving in a circular path and is directed toward the center around which the body is moving

Radial Direction

along a direction pointing along a radius from the center of an object

Tangential Direction

along the direction of the tangent line perpendicular to the radial direction