Motion with constant angular acceleration

AI Thread Summary
The discussion centers on understanding the calculation of revolutions made by a blade under constant angular acceleration until it reaches full speed. Participants emphasize the importance of using angular equations, which parallel linear motion equations, particularly noting that integration is necessary to determine distance traveled from acceleration. There is a request for assistance in clarifying the second part of the question regarding the number of revolutions. Additionally, there is a suggestion to learn how to post mathematical equations using LaTeX for clearer communication. Overall, the focus remains on solving the problem of revolutions during the acceleration phase.
Zoubayr
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Homework Statement
The blade of a circular saw of diameter 20 cm accelerates uniformly from rest to 7000 rev/min in 1.2 s. What is the angular acceleration? How many revolutions will the blade have made
by the time it reaches full speed?
Relevant Equations
w=2πf
w=w_o +at
CamScanner 12-04-2022 20.26.jpg


I am not understanding the 2nd part of the question where it is asked about how many revolutions will the blade make when it reaches full speed. Please help
 
Last edited by a moderator:
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Please learn how to post math equations using LaTeX. Your answer above looks like "Gio rad/s^2". There is a LaTeX Guide link below the Edit window to help you out. Thanks.

Zoubayr said:
I am not understanding the 2nd part of the question where it is asked about how many revolutions will the blade make when it reaches full speed.
The angular equations (position, velocity, acceleration) are analogous to their linear counterparts. For linear motion, what mathematical operation do you use (twice) to go from acceleration to distance traveled? :smile:
 
integration
 
Zoubayr said:
...
I am not understanding the 2nd part of the question where it is asked about how many revolutions will the blade make when it reaches full speed. Please help
Let's divide the time during which the acceleration happened into 12 tenths of one second.
How many times the blade completed a full turn within the 0 to 0.1 second?
...
...
How many times the blade completed a full turn within the 1.1 to 1.2 second?
 
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