You are packing for a trip to another star. During the journey, you will be traveling at 0.99c. You are trying to decide whether
you should buy smaller sizes of your clothing because you will be thinner on your trip due to length contraction. You also plan to save money by reserving a smaller cabin to sleep in because you will be shorter when you lie down. Should you (a) buy smaller sizes of clothing, (b) reserve a smaller cabin, (c) do neither of these things, or (d) do both of these things?
For length contraction : Is calculated considering the observer moving at a speed that is relative the object at rest applying this formula
L = (l)
where l = Measured distance from object at rest, L = contracted measured in relation to the observer , v = speed of clock , c = speed of light
you will do neither of these things because before you can make such decisions who have to view the object in this case yourself from a different frame from where you are currently are, if not your length and width will not change hence you can't make such conclusions/decisions .
You should not go into the left side of the roadway when within 100 feet of the crossing. Moreover, you should also turn on your turn signal when within 100 of a turn. These precautions prevent accidents as it makes clear to other drivers what your intentions are and drivers making turns are not endangered.