Two trains 300 metres and 360 metres long are running in the same direction with speeds of 216 kmph and 162 kmph .In how much time will the first train cross the second? A) 54sec B) 44sec C) 40sec D) 14sec
ANSWE: B
Explanation:
Length of the 1st train=300m
Length of the 2nd train=360m
Speed of the first train=216kmph
Speed of the second train=162kmph
Relative speed =(216-162)kmph
=54kmph.
Convert km/hr into m/s
=(54*5/18) m/s
=15 m/sec.
Time taken by the trains to cross each other=Time taken to cover (300+360)m at 15 m/s
=(660/15) sec
=44 sec
Therefore the first train cross the second at 44 sec.