1.Two trains 100 meters and 120 meters long aer running in the same diredtion with speeds of 72 km/hr and 54 km/hr. In how much time will the first train cross the seconds?
A. 40 sec B. 44 sec
C. 46 sec D. 48 sec
OPTION:B
Relative Speed of trains = (72 - 54) km/hr
= 18 km/hr
= (18 x 5 /18) km/hr
= 5 m /sec.
Time taken to cover = (100 + 120) m/sec
= (220 / 5 ) sec
= 44 sec
