- #1
spaghetti3451
- 1,344
- 33
Homework Statement
The following is Exercise 2.1 from from Ray d'Inverno's 'Introducing Einstein's Relativity.'
(a) Write down the Galilean transformation from observer ##S## to observer ##S'##, where ##S'## has velocity ##v_1## relative to ##S##.
(b) Find the transformation from ##S'## to ##S## and state in simple terms how the transformations are related.
(c) Write down the Galilean transformation from ##S'## to ##S''##, where ##S''## has velocity ##v_2## relative to ##S'##.
(d) Find the transformation from ##S## to ##S''##.
(e) Prove that the Gailiean transformations form an Abelian (commutative) group.
2. Homework Equations
3. The Attempt at a Solution
(a) My answer is $$x' = x - v_1 t,\ y'=y,\ z'=z,\ t'=t,$$ which matches with the textbook answer. So, no problem here.
(b) My answer is $$x = x' + v_1 t,\ y=y',\ z=z',\ t=t',$$ which again matches with the textbook answer. So, no problem here.
(c) My answer is $$x''=x'- v_2 t,\ y''=y',\ z''=z',\ t''=t',$$ but the textbook answer is $$x''=x'+ v_2 t,\ y''=y',\ z''=z',\ t''=t'.$$
(d) My answer is $$x''=x- ( v_ 1 + v_2 ) t,\ y''=y,\ z''=z,\ t''=t,$$ but the textbook answer is $$x''=x+ ( v_ 1 + v_2 ) t,\ y''=y,\ z''=z,\ t''=t.$$
Can someone please tell me if my answers are wrong, or if the textbook answers are wrong?