use Special Relativity Just help me confirm some of these answers. I have doubts on numers 1, Train goes (3/5)c relative to tracks. When the back end is opposite point A on the tracks, and the front end if opposite B then lightning strikes the two ends simulatneously according to a passenger on the train. According to passengers the train is 60m long so answer these question... 1) Which flash occured first from the viewpoint of an obserer standing by the tracks? WEll this is the opposite of simultaneity. In order for someone to see both flashes on the train simulateneously, then the flash from point B is the one which occured first from the stationary observers point of view. 2) How long is the movinbg train from the obserers point of view? Since 'moving objects appear smaller', then observed length L = 60 (root (1-9/25)) which is 48. 3) How far apart are points A and B on the tracks form the viewpoint of an obserer on the track? err since the two flashes did occur simultaneously as per the length of the train which he observed then the distance would haev been 48m 4) How far apart are A and B from the viewpoint of observer on train? Since it did occur corresponding to the train's length it would be 60m? 5) According to the observers on the train how much time will tick off one of the tack clocks during the time 20 secs elapse on the train clocks? Should be longer than 20 secs. So it would be 20 times gamma 6) A window on the side of the train has an area of 10 sq metres according to a seated passenger on the train. What is the area of the moving window from the observer on the track's perspective? This is using 2 dimension analysis. Wouldi assume that the window is square or rectangular? But only the lenght would contract and not te height. If L = 2 and H = 5 then L would reduce to 1.6m and thus areai s 8 sq m and if it was vice versa then it would be the same, so it doesnt make a diff, does it? 7) (LAST ONE!) Suppose the train came to rest, then waht would the observer on the tracks say the lenght of the train was? waht it really is, 60! your input into some of the wrong ones such as 1 (i think), 3 and 4 would be greatly appreciated!