MHB What is the angular velocity of a cylinder in rev/hr

AI Thread Summary
The discussion revolves around calculating the angular velocity of an offset press cylinder with a diameter of 13.37 inches and a linear speed of 16.53 ft/sec. Using the formula v = rω, the angular velocity is determined to be approximately 106,821 rev/hr, which some participants initially found surprisingly large. Clarification is provided on the relationship between revolutions and radians, noting that one revolution equals 2π radians. The conversation highlights the importance of understanding these units in equations. Overall, the calculation and unit conversion are confirmed as correct.
karush
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An offset press cylinder has a $13.37\text {in}$ diameter.

The linear speed is $\displaystyle\frac{16.53 \text{ ft}}{\text{sec}}$

What is the angular velocity $(\omega)$ in $\displaystyle\frac{\text{rev}}{\text {hr}}$

from $v=r\omega$ then

$\displaystyle\frac{16.53\text{ ft}}{\text{sec}}
\cdot\frac{3600\text {sec}}{\text {hr}}
\cdot\frac{1}{6.685\text{ in}}
\cdot\frac{12\text { in}}{\text {ft}}
\approx\frac{106821\text{ rev}}{\text{hr}}$

this ans looks to large?
 
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Re: what is the angular v of a cylinder in rev/hr

You answer is correct...it is spinning many times per second and there are many seconds per hour. :D
 
Re: what is the angular v of a cylinder in rev/hr

well that cool...

I still don't know how to really deal with the words "rev" and "rad" in an equation?
 
Re: what is the angular v of a cylinder in rev/hr

karush said:
well that cool...

I still don't know how to really deal with the words "rev" and "rad" in an equation?
A rev(olution) is once around the circle. This corresponds to an angle of 2pi radians. Thus 1 rev = 2pi rad.

-Dan
 
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