Question 1: An event occurs at x'=60m, t'= 8*10^-8s in frame S' (with y'=0 and z'=0) The frame S' has a velocity of 3c/5 in the x direction with respect to the frame S. The origins of S and S' coincide at t=0,t'=0. What are the space time coordinates of the event in S? Just want to make sure I'm using the Lorentz formulas properly.. ɣ=(1 - v2/c2)-1/2 x = ɣ(x'+vt) = (1-(9/25))-1/2*(60+(3c/5)*(8*10^-8))=93m t = ɣ(t' + (vx'/c^2)) = (1-(9/25))-1/2*((8*10^-8)+(3c/5c^2)*(60))=45s (For some reason I think this is very wrong) Question 2: The space time coordinates of two events measured in the frame S are as follows: Event 1: x1=xo, t1=xo/c Event 2: x2=2xo, t1=xo/2c (a) There exists a frame in which these events occur at the same time. Find the velocity of this frame with respect to S. (b) What is the value of t at which both events occur in the new frame. (a) Would doing the following work? ɣ(t1 + (vx1/c2))=ɣ(t2 + (vx2/c2)) then solve for v which gives v=-c/2 (again I don't think this is right) (b) ɣ=(1 - v2/c2)-1/2 Then using the value of v from a and the equation t'=ɣ(t - vx/c2) solve for t' Any help on this would be greatly appreciated.... This is a lot more confusing than I first anticipated.