# Frequency and angular frequency, rotations per second.

Saw on internet some equations to convert from frequency in hertz to mph. Some equations need a gear ratio while others do not. I found the equation mph = circumference * RPM * 60. Now, it makes sense and if use dimensional analysis I found 1Hz = 60 RPM and 60Hz = 3600 RPM. When calculated for a diameter of a motor shaft with a blade of 30 inches the mph for 1 hz and up to 60Hz is huge. Not at what I see the blade turn at. I got for 60Hz 339,120 inches/sec and 28,260 ft/sec.

Overall, I want to relate hertz to a speed in mph to mentally understand how fast a hertz is?

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freq to mph conversion help

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Saw on internet some equations to convert from frequency in hertz to mph. SOme equations need a gear ratio while others do not. I found the equation mph = circumference * RPM * 60. Now, it makes sense and if use dimensional analysis I found 1Hz = 60 RPM and 60Hz = 3600 RPM. When calculated for a diameter of a motor shaft with a blade of 30 inches the mph for 1 hz and up to 60Hz is huge. Not at what I see the blade turn at. I got for 60Hz 339,120 inches/sec and 28,260 ft/sec.

Overall, I want to relate hertz to a speed in mph to mentally understand how fast a hertz is?

The motion of a particle is called periodic if the motion is repeated after a certain time interval. It may be the motion on a circular ...

#### Solution Summary

The solution is the explanation for the basic idea for rotational frequency and the angular velocity. The concept of units rps, rpm, and hertz is discussed. Conversion from angular velocity to the linear speed is discussed.