unit problem-rad/s to Hz,1/s

I'm new to MathCad,And I have some dificulties When I try to calculate natural frequency for a system.I find the unit can not convert rightly from rad/s to Hz,

As you can see in the attached worksheet,when I change the unit of the circular frequency from rad/s to Hz,the value 144.644 will not change.Does the system see them as the same unit?but I know that the circular frequecy is not same as frenquency.

Thanks!

Best Regards!