Two boatman must swim across the river from point A to point B . One of them sends a boat on the line AB and on reaching the opposite shore, he is at the point C(figure). In order to reach point B, it moves upstream from point C to point B.

The second boatman guides the boat so that it directly goes B. Which of them will get to point B faster, and how many times ? speed of boats on the water in both cases is the same and equal to V=5 m/s, the rate of flow of water is 3m/sec. the width of river is 100 m.

Options

A. The first boatman reaches first
B. The second boatman reaches first
C. the difference between their time of rowing is 25 sec
D. Distance BC is 60 m

Answer

BCD

Explanation

`t_(1)=d/(v_(nr))=100/5 =20 sec`.

`=100/(sqrt(5^(2)-3^(2))) =25 sec`
`x=20 xx3=6m`
`t'_(1)=60/(r_(mr)-v_(r))=60/(5-3) =30 sec`
`t_("1 total")=20+30=50 sec`.