Changes

==Rotational Kinematics==

==Rotational Kinematics==

Rotational kinematics involve describing the motion of rotating objects without understanding the forces that cause them to undergo that motion. It has many similarites to linear motion. Instead of [[displacement]] (distance) in linear mechanics, rotational mechanics considers angular displacement which is the angle something has rotated by. Similarly, [[velocity]] (rate of change of displacment) becomes angular velocity, the rate of change of angular displacement over time. Normally the Greek letter θ is used to denote angular displacement, an ω (omega) is used to denote angular velocity and α to denote angular acceleration. Angular displacement has units of [[radians]] so angular velocity has units of radians per second. These quantities can be related to each other through:

Rotational kinematics involve describing the motion of rotating objects without understanding the forces that cause them to undergo that motion. It has many similarites to linear motion. Instead of [[displacement]] (distance) in linear mechanics, rotational mechanics considers angular displacement which is the angle something has rotated by. Similarly, [[velocity]] (rate of change of displacement) becomes angular velocity, the rate of change of angular displacement over time. Normally the Greek letter θ is used to denote angular displacement, an ω (omega) is used to denote angular velocity and α to denote angular acceleration. Angular displacement has units of [[radians]] so angular velocity has units of radians per second. These quantities can be related to each other through:

:<math>

:<math>

*<math>\omega^2 = \omega_0^2 + 2 \alpha (\theta - \theta_0)</math>

*<math>\omega^2 = \omega_0^2 + 2 \alpha (\theta - \theta_0)</math>

where θ₀ is the inital angular displacement and ω is the final angular velocity.<ref>[http://hyperphysics.phy-astr.gsu.edu/hbase/rotq.html#drot Rotation equations on hyperhpysics]</ref>

where θ₀ is the initial angular displacement and ω is the final angular velocity.<ref>[http://hyperphysics.phy-astr.gsu.edu/hbase/rotq.html#drot Rotation equations on hyperhpysics]</ref>

==Vector Nature of Angular Velocity==

==Vector Nature of Angular Velocity==

==Angular Momentum==

==Angular Momentum==

A key quantity in linear mechancis is [[momentum (physics)|momentum]]. Unsuprisingly, there is a rotational equivalent known as "angular momentum" and this too is a pseudovector. It is defined as the [[cross product]] of the position vector of a particle with its linear momentum:

A key quantity in linear mechancis is [[momentum (physics)|momentum]]. Unsurprisingly, there is a rotational equivalent known as "angular momentum" and this too is a pseudovector. It is defined as the [[cross product]] of the position vector of a particle with its linear momentum:

:<math>

:<math>

{{reflist}}

{{reflist}}

==See Also==

==See also==

*[[Angular impulse]]

*[[Angular impulse]]

*[[Torque]]

*[[Torque]]