Question

A train starts from rest. It moves through 1km in 100s with uniform acceleration. What will be its speed at the end of 100s.
@mary.rojas @xxAshxx

Answer 1

It starts from rest. So, u = 0
Distance traveled = s = 1 km= 1000 m
Time of travel = t = 100 sec

Substituting in s = u*t + (1/2)*a*t^2 (where a is the acceleration):
1000 = 0*t + (1/2)*a*100^2
1000 = a*5000
a = 0.2 m/sec^2

Next, substituting in v^2 - u^2 = 2*a*s (where v is the speed at the end of 100 sec):
v^2 - 0^2 = 2*0.2*1000
=> v^2 = 400
=> v = 20 m/sec

So, speed at the end of 100 sec is 20 m/sec.
FROM http://answers.yahoo.com/question/index?qid=20121225234317AAGQbqp

Answer 2

@imtiaz7 sorry,

Answer 3

@xxAshxx no problem nothing anyone in world who is master in all subjects.

Answer 4

@imtiaz7 lol...:-)