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#1 2017-02-13 14:29:36

Oran2009
Member
Registered: 2016-06-13
Posts: 21

Vectors Question - Direction and Speed

Problem:

A skiff leaves a dock and heads toward a house across the river. The house is at a bearing of

from the dock. There is a 1 mile per hour current blowing due east. Determine the speed and direction the skiff would have to maintain so that the skiff's actual speed is 4 miles per hour and moving directly towards the house.

I know you can solve this with vectors and using trigonometry, but how would I do this?

*You can use the law of sines to find the direction, but what about the speed? Is it just 4 miles?

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#2 2017-02-13 20:55:16

Bob
Administrator
Registered: 2010-06-20
Posts: 10,057

Re: Vectors Question - Direction and Speed

hi Oran2009

NPsFe6u.gif

I have shown the resultant vector (DH) with a double arrow.  It is made up from two components, DP and PH.  You know DH and PH so you can use trig. to get DP.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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