Normal force, centripetal force

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jehan4141
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A woman is riding a Jet Ski at a speed of 26 m/s and notices a seawall straight ahead. The farthest she can lean the craft in order to make a turn is 22°. This situation is like that of a car on a curve that is banked at an angle of 22°. If she tries to make the turn without slowing down, what is the minimum distance from the seawall that she can being making her turn and still avoid a crash?

V=26 m/s
Ncos22 = mg
Fc = mv2 / r = Nsin22
v2 / r = gtan22
r = 170.7 meters?

I know that this is the radius of the circle that she is turning on, but is this also the distance from the sea wall? If the wall is in front of her, the radius does not tell you anything about how far your are from the seawall...
 
Before the Jet Sky starts to turn its velocity is perpendicular to the wall. When it is closest to the wall, the velocity is parallel with the wall.

ehild
 
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  • Diagram of a rider on a horizontal blue line heading toward a vertical black wall, with a red circle of radius R tangent to the line below, labelled turn here at the tangent point, and R marked from the circle's centre to the wall and to the top.
    jetski.JPG
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