If a vehicle (bus, train) rapidly stops (or accelerates, or turns), why don't our hair or clothes move from the inertial force? Many times I was sitting in a train, watching closely nearby people.
If the vehicle changes it's movement rapidly (brakes, turns, etc), then obviously, people feel the inertial pseudo-force that might even make them fall. They don't fall, however, since by the power of their muscles they keep their bodies still, and the friction keeps them in place.
All of the above, however, can't affect the movement of one's hair or clothing. I mean - this inertial pseudo-force affects both one's head and hair, doesn't it? Let's assume one is sitting in a train that brakes forcibly, and they're looking in the direction of the movement of the vehicle. They have muscles in their neck, and so they can stop their head from moving and ramming the backrest of a seat ahead; but, they don't have any muscles in their hair! So, if they forcibly make their heads still, their hair should move forward with respect to the head, just as if under the effect of the wind, shouldn't it? (with the wind imitating the inertial force) Same applies to clothing, etc.
I've been watching very closely - no such thing happens. Why...? I've been wondering for some time, and I can't come to an answer.
 A: 
If a vehicle (bus, train) rapidly stops (or accelerates, or turns), why don't our hair or clothes move from the inertial force?

The short answer is that clothes move and you can quickly perform an experiment.
Take a metro train, preferably at a time when it is empty, and put a long scarf (the heavier the better) on one of the horizontal bars people grip to maintain their equilibrium when standing.
Take a sit and watch the scarf as the metro takes curves, accelerates when it leaves stations or slows down while entering stations.
You will see that the scarf moves, it is true, not in a spectacular way but the phenomenon is observable. 
A: It happens, it's just (as Sidd said) not as noticeable. I would like to suggest the following experiment: wear a chain, necklace, or bracelet--something with some dangle to it. You should see that during braking/acceleration it no longer hangs straight down.
A: The inertial force is proportional to both the acceleration of the system and the mass of the object in question. Hair are light, and thus you don't see the effects without severe acceleration. The clothing are worn, and hence supported by one's body. So they won't move till the body does.
