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1. The Lucknow-Indore Express without its rake can go 24 km an hour, and the speed is diminished by a quantity that varies as the square root of the number of wagon attached. If it is known that with four wagons its speed is 20 km/h, the greatest number of wagons with which the engine can just move is
Putting the value, n = 4
we get, k = 2
Now the equation (as k = 2) become,S =
Thus, it means when n = 144, speed will be zero.
Hence, train can just move when 143 wagons are attached
Solution:
Speed = Putting the value, n = 4
we get, k = 2
Now the equation (as k = 2) become,S =
Thus, it means when n = 144, speed will be zero.
Hence, train can just move when 143 wagons are attached