# Http://www.physics.usyd.edu.au/~gfl/Lecture Physics 1901 (Advanced) A/Prof Geraint F. Lewis Rm 557, A29 gfl@physics.usyd.edu.au www.physics.usyd.edu.au/~gfl/Lecture.

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<ul><li> Slide 1 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Physics 1901 (Advanced) A/Prof Geraint F. Lewis Rm 557, A29 gfl@physics.usyd.edu.au www.physics.usyd.edu.au/~gfl/Lecture </li> <li> Slide 2 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Rotational Motion So far we have examined linear motion; Newtons laws Energy conservation Momentum Rotational motion seems quite different, but is actually familiar. Remember: We are looking at rotation in fixed coordinates, not rotating coordinate systems. </li> <li> Slide 3 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Rotational Variables Rotation is naturally described in polar coordinates, where we can talk about an angular displacement with respect to a particular axis. For a circle of radius r, an angular displacement of corresponds to an arc length of Remember: use radians! </li> <li> Slide 4 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Angular Variables Angular velocity is the change of angle with time There is a simple relation between angular velocity and velocity </li> <li> Slide 5 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Angular Variables Angular acceleration is the change of with time Tangential acceleration is given by </li> <li> Slide 6 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Rotational Kinematics Notice that the form of rotational relations is the same as the linear variables. Hence, we can derive identical kinematic equations: LinearRotational a=constant constant v=u+at o + t s=s o +ut+at 2 o + o t+t 2 </li> <li> Slide 7 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Net Acceleration Remember, for circular motion, there is always centripetal acceleration The total acceleration is the vector sum of a rad and a tan. What is the source of a rad ? </li> <li> Slide 8 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Rotational Dynamics As with rotational kinematics, we will see that the framework is familiar, but we need some new concepts; LinearRotational MassMoment of Inertia ForceTorque </li> <li> Slide 9 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Moment of Inertia This quantity depends upon the distribution of the mass and the location of the axis of rotation. </li> <li> Slide 10 </li> <li> http://www.physics.usyd.edu.au/~gfl/Lecture Moment of Inertia Luckily, the moment of inertia is typically; where c is a constant and is </li></ul>