Question

8.
A train starts from rest and
2 points
moves with an acceleration of 2m/sec
square for 10 seconds and then brake
is applied due to which it comes to rest
rate of dit
gh Speed
fusing ver
In the gas
randon
om mover
ind also
e exerted
erted by
alls of the
in next 10 sec. the total distance
travelled will be-
100 metre
200 metre
300 metre
400 metre​

Answer 1

Answer:

In this Journey, the train has accelerated and decelerated motion.

For accelerated motion :

Initial velocity=u=0m/s

acceleration=a=2m/s2

time=t=half minute=30 sec

Final velocity =V=?

From first equation of motion , v=u+at

v=0+2x30=60m/s

So train has travelled 60m/s before brakes are appplied.

Hence the maximum speed attained by train 60m/s.

Distance travelled : From second equation of motion : S=ut+1/2at²

S=0x30+1/2 x 2x 30²

s=900m/s

s=900/1000 =0.9km

c) The position of train at half the maximum speed [30m/s]:=

Let s be the position of train at half the maximum speed 

v²-u²=2as

s=v²-u²/2a

s=30²-0²/2x2

s=900/4=225m

For decelerated motion :

Final Velocity=V=o m/s

initial velocity=u=60m/s

time=60sec

From first equation of motion : v=u+at

0=60+ax60

a=-60/60=-1m/s2

Distance travelled during this part is :

s=ut+1/2at²

=60x60+1/2 (-1x60²)

=3600-1800

=1800m

=1.8km

Hence total distance travelled by train=0.9km+1.8km

=2.7km

Answer 2

300meter

hope it helps you mate......