What are the units for angular velocity in this hydraulic piston mechanism?

AI Thread Summary
The discussion clarifies that the units for angular velocity in the context of a hydraulic piston mechanism are indeed radians per second (rad/s). The user calculated angular velocity using the formula ω = v/r, resulting in 1.25 rad/s. A participant confirmed that while revolutions per second (rev/s) are also a unit of angular velocity, they differ by a factor of 2π from radians per second. The explanation emphasizes that for circular motion, the relationship between linear velocity and angular velocity is consistent with SI units. The final consensus reassures that the correct unit for angular velocity in this scenario is rad/s.
fluidmech
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Homework Statement


Hello, I am doing a mechanisms homework assignment in which a hydraulic piston moves out and moves a link connected to the piston in an angular fashion. I'm just a bit confused about the units of angular velocity and I feel very foolish asking this.


Homework Equations


\omega \times r = v
\omega = \frac{v}{r}


The Attempt at a Solution


v=0.751751\frac{m}{s}
r=0.6 m
\omega=\frac{v}{r}=\frac{0.751751 \frac{m}{s}}{0.6 m} = 1.25 \frac{rad}{s}

Can someone just double check that the units are indeed radians per second? SI units for angular velocity is rad/s.. and this is SI. Just want to double check that it's not rev per second. I know, it's foolish. Thanks in advance!
 
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fluidmech said:

Homework Statement


Hello, I am doing a mechanisms homework assignment in which a hydraulic piston moves out and moves a link connected to the piston in an angular fashion. I'm just a bit confused about the units of angular velocity and I feel very foolish asking this.

Homework Equations


\omega \times r = v
\omega = \frac{v}{r}

The Attempt at a Solution


v=0.751751\frac{m}{s}
r=0.6 m
\omega=\frac{v}{r}=\frac{0.751751 \frac{m}{s}}{0.6 m} = 1.25 \frac{rad}{s}

Can someone just double check that the units are indeed radians per second? SI units for angular velocity is rad/s.. and this is SI. Just want to double check that it's not rev per second. I know, it's foolish. Thanks in advance!

Yes, it's radians/sec. rev/sec differs by a factor of 2pi. To convince yourself, if v=1m/sec and r=1m and the motion is circular then v/r=1/sec but it would take you 2pi seconds to get around the whole circle and make a rev.
 
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