The speed of a passenger train in the USA depends on the type of passenger train that you're riding in.
However passenger trains in the US travel at speeds of between 81 MPH to as fast as 125 MPH.
Most standard passenger trains travel at a speed of 80 MPH to 85 MPH.
As for the Amtrak Passenger trains those trains usually travel at a speed of 100 MPH to 125 MPH which is incredible.
Those Amtrak Passenger trains can get you to your destination pretty fast and usually much faster than going by car.
So when you get on an Amtrak Train be prepared to go for a high speed ride but they are pretty safe and they have good drivers driving the trains.
I've road on an Amtrak Train and I asked how fast it went and they said that it was traveling at a speed of 125 MPH which was incredible.
It was a pretty fun ride and I hope to do it again.