We are here to help with income tax questions.   Your question is about  state sales tax.  You need to explore the sales tax laws of your state with the state itself.

You do have a physical location. It's where you live and conduct your online business. The fact that you are sitting in Utah when you conduct your business creates the physical presence, even if no customers come to your location. Since you have a physical presence in Utah, you must collect Utah sales tax on all sales to customers who are located in Utah. It doesn't matter that you make the sales online.