Rate of current when man go across the width of river in t and t hours.

A man directly crosses a river in time t_1 and swims down the current a distance equal to the width of the river I time t_2 . If u and v be the speed of the current and the man respectively, show that : t_1 :t_2 = sqrt(v + u) : sqrt(v - u)) .

A man can swim in still water at a speed of 4 kmph . He desires to cross a river flowing at a speed of 3 kmph in the shortest time interval. If the width of the river (in hours) and the horizontal distance travelled (in km) are respectively

47.A man can row a boat with 4kmph in still water.If he is crossing a river where the current is 8kmph .The time take to cross the river in shortest path is (k)/(sqrt(3))hr .Where k ' is (width of the river is 8km )

A man can swim in still water at a speed of 6 kmph and he has to cross the river and reach just opposite point on the other bank.If the river is flowing at a speed of 3 kmph ,and the width of the river is 2km , the time taken to cross the river is (in hours)

A man can swim in still water at a speed of 5km//h . Man crosses 1 km width of river along shortest possible path in 15 minutes . What is the speed of river in km/h?

A bridge across the river makes an angle of 30^(@) with the river bank.If the length of the bridge across the river is 60m, Find the width of the river.

From a point on a bridge across a river the angles of depression of the banks on opposite side of the river are 30o and 45o respectively. If bridge is at the height of 30m from the banks,find the width of the river.

Let /_\Q be the net charge flowing across a cross-section of a conductor during the time interval /_\t [i,e. between times t and (t+/_\t) ]. Then, the current at time t across the cross-section of the conductor is defined as

A man who can swim at a speed v relative to the water wants to cross a river of width d flowing with a speed u. The point opposite him across the river is A.