Problems on "Length contraction" 1. The problem statement, all variables and given/known data This is a problem in my text. The idea is that a bar is moving with a high speed (say 0.5c) relative to us. We now want to know what will be the length appeared to us if the bar is parallel, perpendicular and 60 degrees tilted. And we are asked when the bar is tilted, how long is it in the co-moving frame. 2. Relevant equations L=(Lo)/y where Lo is the proper length 3. The attempt at a solution First two are very straight-forward, but I can't understand the difference between the last two questions. I tried to resolve the velocity component but still I could not work it out. Any explanation is appreciated, thank you in advance.