Preeti reached the metro station and found that the escalator was not working. She walked up the stationary escalator in time t1. On other days, if she remains stationary on the moving escalator, then the escalator takes her up in time t2. The time taken by her walk up on the moving escalator will be
t1= time taken at stationary escalator
t2= time taken at moving escalator
t′= time taken in walking up the moving escalator
d= displacement of escalator
V1= Velocity of Preeti
V2= Velocity of escalator
(V1+V2)=dt′, as V1=dt1,V2=dt2
dt1+dt2=dt′⇒t′=t1t2t1+t2