Relative Motion Analysis: Acceleration of rotating disk

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
3 replies · 2K views
_N3WTON_
Messages
350
Reaction score
3

Homework Statement


A slotted link AC is is driven by the peg P connected to a rotating disk. Point A is fixed. Determine the link's angular velocity, [itex]\omega_{ac}[/itex] and acceleration, [itex]\alpha_{ac}[/itex] when the angular velocity and acceleration are [itex]\omega[/itex] and [itex]\alpha[/itex], respectively.
[itex]\omega = 6 \frac{rad}{s}[/itex] CCW
[itex]\alpha = 10 \frac{rad}{s^2}[/itex] CCW
[itex]l_{ap} = 0.75 \hspace{1 mm} m[/itex]
[itex]r_{op} = 0.30 \hspace{1 mm} m[/itex]
[itex]\theta = \frac{\pi}{6}[/itex]
kBBmaLU.png


Homework Equations

The Attempt at a Solution


First, I should state that I am genuinely lost on this problem. I am not sure at all how to go about finding the angular velocity for this one. For the acceleration I was thinking that I could perhaps draw an acceleration diagram and attempt to find the solution that way. Maybe I could do something similar for the velocity? I was hoping someone could sort of push me in the right direction/inform me whether there is a better way to solve this rather than a graphical approach. Any help at all is greatly appreciated. Thanks.
 
Physics news on Phys.org
The diagram uses theta for two different things... probably because they have the same size at t=0.
Play with the setup for different angles to P ... OP has a constand angular velocity so you can redo the sketch for equal times ans get a feel for what is happening.
There are several approaches but try finding the equation of the angle of the link as a function of time aband differentiating.
 
Simon Bridge said:
The diagram uses theta for two different things... probably because they have the same size at t=0.
Play with the setup for different angles to P ... OP has a constand angular velocity so you can redo the sketch for equal times ans get a feel for what is happening.
There are several approaches but try finding the equation of the angle of the link as a function of time aband differentiating.
Awesome, thanks for the reply. One thought I did have was to consider this as a crank and slotted lever mechanism, where the disk is the crank. Could I do an analysis this way? Or would it be too inaccurate?