Question

32.The velocity of water in a river is 2kmph, while width is 400m.A boat is rowed from a point rowing always aiming opposite point at 8kmph of still water velocity. On reaching the opposite bank the drift obtained is

Answer 1

Rowing is done always aiming in perpendicular direction to the flow of the river.
So net velocity of the boat has a velocity of 8 kmph perpendicular to the flow of river and 2 kmph along the flow of river water.

The boat crosses the river in  400 meters / 8 kmph = 1/20 Hours = 3 minutes

In 3 minutes, the boat will travel along the flow of the river
  = 1/20 hours * 2 kmph = 0.1 km

Hence the drift is 0.1 km.

Answer 2

Answer:

Explanation:

Rowing is done always aiming in perpendicular direction to the flow of the river.

So net velocity of the boat has a velocity of 8 kmph perpendicular to the flow of river and 2 kmph along the flow of river water.

The boat crosses the river in  400 meters / 8 kmph = 1/20 Hours = 3 minutes

In 3 minutes, the boat will travel along the flow of the river

 = 1/20 hours * 2 kmph = 0.1 km

Hence the drift is 0.1 km.