Q28 of 43 Page 85

A train moving at a constant velocity of 54 kmhr–1 moves east wards for 30min then due north with the same speed for 40 min. What is the average velocity of the train during this run?

To find: Average Velocity = ?


Now, Total time = (30 + 40) minutes


= 70 minutes


= Hour = Hour


(1 hour = 60 min)


Let,


Eastwards is positive x direction


Northwards is positive y direction


So,


Eastwards : ,


Northwards : ,


Now, Displacement = Velocity × Time


Eastward:



Northward:



So, Total Displacement =


And,


Now, also total time = hr


So,



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