Question

Can someone explain me ,Galileo coordinate system (ı saw it when studyıing relativity)

Answer 1

Galilean coordinate system and Galilean transformation consider time to be invariant regardless of the velocity of the frame of reference.

Galilean transformations are easy and require only knowledge of vector addition and subtraction.
Consider two Galilean coordinate systems, S1 and S2. S2 is moving with a relative velocity vector of v. r1 and r2 are position vectors of a point P in S1 and S2 respectively. Consider that their origins O and O' were coinciding at t=0.

From the figure

r2=r1-vt

Note that we have taken time to be invariant under the transformation .Also,r1,r2,v are vectors.

Answer 2

thank u much but there is a point ı didnt understand why acceleration doesnt change when we take the derivative of velocity ?

Answer 3

Since S2 is ,moving with constant velocity w.r.t to S1, the acceleration will be same in both the frames. Had S2 been accelerating w.r.t. to S1, we would have got different accelerations. This defines inertial and non inertial frames.When frames move with constant velocity w.r.t an inertial frame, the only forces acting on an object are 'real' forces like gravity,contact forces, friction etc. But when it is accelerating, some forces appear which have no physical origin. These are called 'pseudo forces'. This force is nothing but response to inertial of the body.