Panic escape. Figure 2-22 shows a general situation in which a stream of people attempt to escape through an exit door that turns out to be locked. The people move toward the door at speed vS: 3.50 m/s, are each d = 0.25 m in depth, and are separated by L = 1.75 m. The arrangement in Fig.2-22 occurs at time t = 0.(a) At what average rate does the layer of people at the door increase?(b) At what time does the layer's depth reach 5.0 m? (The answers reveal how quickly such a situation becomesdangerous.)

Locked door