A train slow from 108km/hr with a uniform retardation of 5m/s.how long will it take to reach 18km/hr andwhat is the distance covered

Answer 1

guessing the retardation (acceleration) is 5 m/s^2

108 km/hr * (1 hr/ 3600 s) * (1000 m / km) = 30 m/s

18 km/h = (108 km/h) / 6 = 5 m/s

FYI ... ≈ .5 g acceleration seems fairly high for a train