Solve Angular Velocity & Acceleration - Dimensional Analysis

AI Thread Summary
The discussion focuses on solving for angular velocity and acceleration using dimensional analysis. The user calculates linear velocity and angular velocity, finding that a radius of 0.4m results in an angular velocity of 5.535 rad/sec. They also compute angular acceleration as 24.52 rad/s² based on the change from an initial angular velocity of 0 to a final of 5.535 over a time of 0.225756 seconds. Participants emphasize the importance of understanding the simpler parts of the problem before tackling more complex aspects. The conversation highlights the need to consider how variations in time affect the results.
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Hi guys,

Please see attached image - it's the part highlighted yellow that I'm stuck on.

Here is what I got for linear velocity and angular velocity. (requested by mod)

Thanks!
c) Angular to velocity
Dia=0.8m .. rad=0.4m
v (linear velocity) = r (radius of circle) * omega (angular velocity)
lets rearrange
linear velo (2.214 m/s = 0.4m* angular)
2.214 / 0.4

=5.535 rad/sec

d) Angular acceleration of the drum
initial angular velo = 0
final angular veloc=5.535
time=0.225756
formula=
angular acceleration = initial angular velo. (0) - final angular acc. (5.535) / t (0.225756)

angular acceleration=24.52 rad/s^2
physics1.JPG
 
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PF rules require you to provide your own efforts. What are your thoughts on the part of the problem you are asking about?
 
Sorry I didn't realise that.

I pretty much don't understand the question and where to go with it
 
In addition to what @Orodruin has said, can I add this?

Before you get onto the 'hard' part of the question, you will need to deal with the ‘easy’ parts, a) – f), correctly.

Ask yourself: “If A (the time taken) is very large, would I expect different answers compared to A being very small?”.

E.g. imagine A = 3600s and then imagine again with A = 1s).
 
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