Unit 7: Torque and Rotational Motion

Rotational motion is the motion of an object around an axis or a fixed point.

Linear kinematics is the study of motion of objects in a straight line.

Rotational kinematics is the study of motion of objects that rotate around a fixed axis.

Force is a push or pull that can cause a change in motion.

Torque is the force that causes an object to rotate about an axis.

Mass is the amount of matter in an object.

Moment of inertia is the resistance of an object to rotational motion.

Acceleration is the rate at which an object changes its velocity.

Angular acceleration is the rate of change of angular velocity with respect to time.

Fnet = ma

Tnet = Ia

Velocity is the speed and direction of an object's motion.

Angular velocity is the rate of change of angular displacement with respect to time.

Angular displacement is the angle through which an object rotates.

The linear velocity and acceleration of a point on a rotating object are equal to the product of the angular velocity and acceleration and the radius of the circle.

Center of mass is the point in an object or system that moves as if all the mass were concentrated at that point.

COM = (m1r1 + m2r2 + ... + mn rn) / (m1 + m2 + ... + mn)

The right-hand rule is a rule used to determine the direction of torque.

τ = r x F

The unit of torque in the US customary system is the foot-pound (f