CPU usage in virtual machines

CPU usage in virtual machines

I have a host machine with 1 logical processor running at 2.0GHz with 2
VMs running. Each VM is running at 100 % utilization (according to Task
manager inside the VM). I realize this "100%" is not accurate in the sense
that actually, each VM is utilizing about 50% of available CPU resources
of the host machine. Only if I stopped one of the VMs would the running VM
really be using 100% of the physical CPU.
How does this process work? If the physical processor runs at 2.0GHz, are
we essentially creating two virtual processors that each run at 1.0GHz? So
when we see 100% utilization on both VMs, we are talking about 100% of
1.0GHz on each? How is that percent utilization derived in the first
place?
Thank you!