Question

PLEASE HELP! I WILL MARK BRAINLIEST! if you don’t know, search from google and find good answers, i can’t google because i have lots of hw

Answer 1

Answer:

1)Let, u be the initial velocity

Retardation is a Time is t

Velocity is v

We know, v = u + at

As, the train stops so v = 0 Time t = 20s

Retardation a = 15m/s

Therefore, according to the formula u = 0 + (15*20) = 300 m/s.

2)Acceleration=change in velocity /time

i.e v-u/t

initial velocity =u = 18km/h X 5/18=5m/s

final velocity= v =36km/h X 5/18 = 10m/s

acceleration=v-u/t

                    =10-5/5

                     =1m/s2

hence acceleration in 1 meters per second

Answer 2

Explanation:

1---Let, u be the initial velocity

Retardation is a Time is t

Velocity is v

We know, v = u + at

As, the train stops so v = 0 Time t = 20s

Retardation a = 15m/s

Therefore, according to the formula u = 0 + (15*20) = 300 m/s.