There is a laboratory in which there is a string tied to a bob on the earth.Consider the earth is perfect sphere ,rotates on its own axis in a circular path with uniform angular velocity. Main Q of this concept is to find apparent weight of the object but I have some more Q related to this.
So , I tried to draw every possible frame of reference I can. Pls check if it is correct or not.
In earth frame of reference , I excluded the centripetal force and added a pseudo force. My confusion in this part is that if as an NIF , I look at the box from earth. Does it mean I am inside the earth on the ground or can I say I am a person running on the earth surface (I.e as if I am 1million feet in height )who has same acc as that of the box on the ground of earth or are both the situations same in meaning ?.
My Q 1:is that is it possible if we can take a non inertial frame due to which when I consider the FBD of the box , the mg or N force is not present.
It is more like I also wish to know when do cos die the mg , N forces. I am not getting when to exclude them in NIF.