Question

a train decrease it velocity 80 km/h to 50 km/h in 8 seconds. calculate it acceleration

Answer 1

hey dear may this help you.......

first of all as time is in sec....convert velocity into m/s.....so

50km/hr = 13.8m/s

80km/hr = 22.2m/s

now in formula v=u+at

v= 13.8m/s

u=22.2m/s

t=8sec

a=?

therefore using v=u+at

                          a =v-u/t

                         a = 13.8 - 22.2/8

                         a = -1.05

thus the retardation is of -1.05m/s^2

hope it helps!!

Answer 2

u =  80km/hr = 80 * 5/18 m/s = 22.22 m/s
v = 50km/hr = 50*5/18 m/sec  = 13.88 m/s
t = 8 sec
so, a = v-u/t
 = 13.88-22.22/8
 =  -8.34/8
 = -1.0425 m/s^2