Question

please ans. this fast....Rajdhani Express leave Delhi for Jaipur at a speed of 120km/h . After 90 minutes,another trian Delhi Express Leaves for jaipur for Delhi at a speed of 100km/h . Whenthe two traians cross EAch other wich trian is closer tro jaipur??

Answer 1

this question is incomplete .you have to specify the distance between the two places and also be a little more clear.

Answer 2

Speed of train A travelling from Delhi to Jaipur = 120 km/hr

Speed of train B travelling from Jaipur to Delhi = 100 km/hr
Now, it is given that the train B starts after 90 min than that of the train A.
Suppose the train A reaches the point P after 90 minutes.

Distance covered by the train A in 90 minutes = 120×9060=120×32=180 km

Let the total distance between Delhi and Jaipur = (x + 180) km
Here x = distance between point P and Jaipur.
After the train A has reached point P, let after t hours both the trains meet at point Q.
As the trains are moving towards each other so the relative velocity of train A with respect to train B = 120 + 100 = 220 km/h

Now, t = x220 hours. Now, distance travelled by train A in t hrs = 6x11 km Now, distance travelled by train B in t hrs = x − 6x11 = 5x11 km So, when the two trains cross each other, then distance travelled by train A =[ 180 + 6x11] km distance travelled by train B = 5x11 km Since the train A is travelling towards Jaipur anthe train B is travelling towards Delhi,so, it is clear that when the 2 trains meet each other, they are from same distance Jaipur.After crossing each other, the train A will be closer to Jaipur as it is heading towards Jaipur.