Boats And Streams


DownStream:- In water, the direction along the stream is called downstream

UpStream:-  The direction against the stream is called upstream.

If the speed of a boat in still water is u \(\mathrm{km} / \mathrm{hr}\) and the speed of the stream is \(\mathrm{v}\;\mathrm{km} / \mathrm{hr},\)  then:- 

                Speed downstream = \((u+v) \mathrm{km} / \mathrm{hr}\)

                Speed upstream = \((u-v) \mathrm{km} / \mathrm{hr}\)

If the speed downstream is a \(\mathrm{km} / \mathrm{hr}\) and the speed upstream is b \(\mathrm{km} / \mathrm{hr}\)  , then:-

               Speed in still water = \(\frac{1}{2}(a+b) k m / h r\)

               Rate of stream = \(\frac{1}{2}(a-b) k m / h r\)