(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Eriks disabled boat is floating at a stationary location 3 miles East and 2 miles North of Kingston. A ferry leaves Kingston heading due East towards Edmonds at 12mph. Erik leaves the sailboat in a dingy heading due South at 10ft/sec (hoping to intercept the ferry). Edmonds is 6 miles due East of Kingston.

a) Compute Eriks spead in mph and the ferrys speed in ft/sec.

b) Impose a coordinate system of Erik and the ferry. What are Eriks and the ferrys locations at time 0, 30sec, 7min, and 1 hour? What are the distances between them at each time-point?

c) Explain why Erik misses the ferry.

d) After 10 minutes a Coast Guard boat leaves Kingston heading due East at a speed of 25ft/sec. Will the Coast Gaurd boat catch the ferry before it reached Edmonds? Explain.

2. Relevant equations

distance = rate X time

d=sqrt (x2-x1)^2 - (y2-y1)^2

3. The attempt at a solution

a) Eriks speed is 10ft/sec or 6.818 mph

The ferrys speed is 12mph or 17.604 ft/sec

b)Eriks orgin is (3,2)

Ferry orgin is (0,0)

I am confused with how to use the coordinates to calculate their positions at certain time-points.

I think to find the distances between them at the given time-points I use the following equations and substitute them into the distance formula:

Erik: (3, 2-6.818) Ferry: (12,0)

Any help is appreciated!

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# Homework Help: Imposing Coordinates

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