Question

two trains moving in opposite direction cover same distance "D" in 30min if the train are moving in north-south direction what will be their displacement in​

Answer 1

Answer:

Both identical trains have speed of xand y m/s and sum of their lengths be D

Thus, t=  

(x+y)

D

​  

=3

When speed of one is increased by 50%: t=  

(1.5x+y)

D

​  

=2.5

3x+3y=3.75x+2.5y

0.5y=0.75x

y=1.5x

D=3(x+y)=3(2.5x)=7.5x

Thus, time for train moving in same direction=  

(y−x)

D

​  

=  

(1.5x−x)

7.5x

​  

=  

0.5

7.5

​  

=15 s

Explanation: