train a moving at 30km/hr passes station at 08:00.A train B travelling the same way at 45km/hr passes this station at 08:30, at what time will train B overtake A
please can someone explain to me
between 8:00 and 8:30, A has gone 15 km
The speed difference B-A = 15 km/hr
So, since B is 15km behind A at 8:30, it will take 1 hour to make up the distance.
To solve this problem, we need to find out how long it will take train B to catch up to train A after it passes the same station.
Let's first calculate the head start that train A has on train B. Train A passes the station at 08:00, which means it has been traveling for 30 minutes by the time train B starts at 08:30.
We can calculate the distance traveled by train A during this time using the formula: distance = speed × time.
The speed of train A is given as 30 km/hr, and the time is 30 minutes (0.5 hours).
Therefore, the distance traveled by train A is: distance = 30 km/hr × 0.5 hr = 15 km.
Now, we need to find out how long it will take train B to cover this 15 km and catch up to train A. To do this, we need to know the relative speed of train B with respect to train A.
The relative speed is the difference in speeds between the two trains. In this case, train B is faster, so the relative speed is: relative speed = speed of train B - speed of train A.
Therefore, the relative speed is: relative speed = 45 km/hr - 30 km/hr = 15 km/hr.
Now, we can calculate the time it will take for train B to overtake train A by dividing the distance (15 km) by the relative speed (15 km/hr):
time = distance / relative speed = 15 km / 15 km/hr = 1 hour.
Since train B starts at 08:30, it will take 1 hour to catch up to train A, so it will overtake train A at 09:30.