Question

45
3. A train starts from rest and accelerates uniformly at 100 ms? for 10 s. It then maintains a
constant velocity for 20 s. Then the brakes are applied ant the train is uniformly
retarded. It comes to rest in 5 s. Draw velocity-time graph and use it to find
i) the maximum velocity reached
ii) the retardation in the last 5 s
total distance travelled
iv) The average velocity of the train.
Draw velocity time graph and use it

Answer 1

Answer:

i) the maximum velocity reached

Answer 2

Explanation:

i) u=0

a=100m/s²

t=10s

Maximum Velocity=u+at

0+(100×10)

1000m/s

ii) a= v-u/t

0-1000/5

-200m/s

s= ut+1/2at²

(1000×5) + 1/2 ×(-200)×5×5

5000-2500

2500m