# Trigonometrywhat is the angular velocity of a cylinder in rev/hr

#### karush

##### Well-known member
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???

#### MarkFL

Staff member
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.

#### karush

##### Well-known member
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?

#### topsquark

##### Well-known member
MHB Math Helper
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?
A rev(olution) is once around the circle. This corresponds to an angle of 2pi radians. Thus 1 rev = 2pi rad.

-Dan