Hi this problem confuses me :(adsbygoogle = window.adsbygoogle || []).push({});

A sailor wants to travels due east at a velocity of 15km/h with respect to a coordinate system fixed to the ground.

The sailor must contend with the gulf stream, which moves north at 5 km/h. With which veolcity with respect to the water should the sailboat proceed under sail?

to try solve it I set :

V_{bg}= velocity of boat relative to ground.

V_{wg}= velocity of water relative to ground.

V_{bw}= velocity of boat relative to water.

now I wrote: V_{bg}= V_{bw}+V_{wg}but For me it does not fit.

What would fit is :

V_{bw}= V_{bg}+V_{gw}

hereVis not defined in the problem!_{gw}

please can someone can help me?

Also, to find the angle θ of the boat, I am confused about what ( and where)put in the equation θ =tan^{-1}(y/x)

Thank you

brad

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# Homework Help: Relative position

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