# Inertial Frame and Non Inertial Frame

#### onursamed

Hello everyone I have 2 Questions for you. Thank you for your all answer.
1) Can we say that a nonrotating frame with its origin at the center of the earth (earth-centered frame) is inertial, even though the earth is accelerating and rotating?
2) Can we say that a nonrotating frame with its origin at a point on the surface of the earth (earth-fixed frame) is inertial, even though the earth is accelerating and rotating?

#### Woody

Strictly speaking no to both.
However the acceleration due to the rotating earth is small enough to allow it to approximated as an inertial frame for most purposes.