SOLUTION: a boat has a speed of 9.0 km/hr, in still water and is traveling down a river with a current of 2.0 m/s. What will be its "riverbank" velocity going down and then upstream? At what

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Question 732463: a boat has a speed of 9.0 km/hr, in still water and is traveling down a river with a current of 2.0 m/s. What will be its "riverbank" velocity going down and then upstream? At what angle would this boat have to travel across the river in order to move straight across? Thank you :D
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Going upstream, the speed along the riverbank
is +9+-+2+=+7+ m/s
Going downstream, the speed along the riverbank
is +9+%2B+2+=+11+ m/s
The boat should travel at angle +a+,
( heading against the current )
so that +sin%28a%29+=+2%2F9+
This is +9+ m/s at angle +a+, and
+2+ m/s will bring the boat straight across.
You can find +a+