Question

A train starts from rest and accelerates uniformly for 30 seconds to acquire a Velocity of 108 km/h. It travels with this velocity for 20 minutes. The driver now applies brakes and the train slows down uniformly to stop after 20 seconds. Find the total distance covered by the train.​

Answer 1

Answer:

$36750 \: m$

Explanation:

When the train starts from rest,

u= 0,

t= 30s,

v= 108 km/h = 108 × 5/18 = 30 m/s.

Now,

a= v-u/t = 1 m/s².

Distance ,S1 = ut + 1/2 at²

= 0 + 1/2 × 1 × 30 × 30

= 450 m.

At uniform velocity of 30 m/s for 20 min, i.e., 1200s,

Distance, S2 = 30 × 1200 = 36000 m.

Now,

On applying brakes,

t= 20s,

u= 30 m/s,

v= 0.

a= v-u/t = 0-30/20 = -1.5 m/s²

Distance S3 = v² - u²/2a

= 0 - (30)² /2 × 1.5

= 300 m

Therefore,

The total distance traversed = S1 + S2 + S3

= (450 + 36000 + 300) m

= 36750 m

Answer 2

ANSWER = 36750 meters

To do this question first you have to convert units into SI units means meter, second,

in question velocity is given 108 KM/s

convert it into m/s by multiplying with 5 and divided by 18

now you get velocity equal to 30 m/s