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Rotational motion

have a question.
diameter of a rotor is 7.60m and rotational speed of 450 rev/min. calculate speed of tip. anywell would be welcomed
 

Pyrrhus

Homework Helper
2,160
1
What equation relates both?

[tex] v = \omega r [/tex]
 
the answer in the back of the book says179 m/s. but when i try that formula it comes out as 311.6
 

Pyrrhus

Homework Helper
2,160
1
Oh sorry, yes the book is right

A rev is equal to 2 pi radians, and a minute is equal to 60 second. You need to homogenize (spl?) your units.
 
the rev/min is 47.81 rev/sec
 
sorry its 47.12 rad/s
 

Pyrrhus

Homework Helper
2,160
1
Multiply it with 3.8 m
 

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