2022-10-03 09:44:28 +00:00
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---
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author: Akbar Rahman
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date: \today
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2022-11-04 12:39:44 +00:00
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title: MMME2046 // Dynamics
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tags: [ mmme2046, uon, uni, dynamics ]
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2022-10-03 09:44:28 +00:00
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uuid: 98a5449a-02d3-492c-9d0e-3d3eb74baab5
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---
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# Machine Dynamics
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- Rigid Body - Distances between any two particles on a body remain constant---in real life we are
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looking for negligible deformation
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2022-10-17 09:49:09 +00:00
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# Lecture 2 (W04/41)
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## Relative Motion
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where $_{BA}$ is read as "$B$ as seen by $A$".
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These equations must be treated as vectors.
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# Lecture 3 (W05/42)
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## Instantaneous Centre of Rotation
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This is a point with zero velocity at any particular moment.
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$$v_A = 0$$
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$$v_B = v_{BA}$$
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To find the centre of rotation you can draw to perpendicular lines to velocities from two non
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stationary points.
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The centre of rotation will be where the lines intersect.
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## Point Velocity Projections on Joining Axis
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Take two points $A$ and $B$ and their velocities at one instant
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\begin{align}
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v_B &= v_A = v_{BA} \\
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\text{then } \pmb{v_B} || AB &= \pmb{v_A} || AB + \pmb{v_{BA} || AB \\
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\text{but } \pmb{v_BA} || AB &\equiv 0 \text{(since $\pmb{v_BA} \perp AB$)} \\
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\text{or } \pmb{v_B| || AB &= \pmb{v_A} || AB \\
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v_B\cos\beta = v_A\cos\alpha \\
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\end{align}
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# zack.jpg
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2022-10-03 09:44:28 +00:00
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2022-10-03 10:06:34 +00:00
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