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Lava
Sep29-04, 02:53 AM
Hi, I'm struggling through this question and can't seem to come up with an answer :(

The question is: A student in a boat wants to cross the river from point A to point B (see diagram). The current of the river is v (2.0km/h, flowing east); speed of the boat in still water is u (5.0km/h). The point B is at an angle θ (60˚) from the distance L (0.25km) measuring the width of the river.
pt B
--------------------
..\........|
....\......|.L.......V
......\....|....... ---->
........\θ|
..........\
--------------------
pt A
(diagonal line = path of boat, the perpendicular line to the river side is the length L) Ignore the dots...I don't know how to set empty spaces

Can anyone please help me? Thanks for your time

Tide
Sep29-04, 03:11 AM
So, what exactly is the question?

Lava
Sep29-04, 08:43 AM
Sorry about that..the question is how long would it take the student to travel from point A to point B. Thanks