Something strange about new york city subways

[Starwing123]

I've always noticed something strange about new york city subways. When they start to slow down, you feel a force pushing you forward, which seems fine. However, the subway car actually stops, you feel a jerk backward at that moment. Is there an explanation for this?

 

[russ_watters]

The concept is, in fact, called "jerk": http://en.wikipedia.org/wiki/Jerk_(physics )

Since you are leaning backwards you just about fall over since the rate of change of acceleration is faster than you can react to.