In: Physics
A woman is riding a Jet Ski at a speed of 30 m/s and notices a seawall straight ahead. The farthest she can lean the craft in order to make a turn is 23
This problem is analogous to the classic problem of a car rounding
a banked curve. The equation for centripetal force in 2 dimensions
is
(1) Fc = m(v^2)/r
The woman leaning on the jet ski is like the car sitting on a
banked road of angle (b). The horizontal force pushing the jet ski
in towards the center of the curve acts as the centripetal force
and is given by
(2) Fc = Fn sin(b), where Fn is the normal force
Furthermore, the normal force on the incline is related to the
gravitational force by
(3) Fn = mg / cos(b)
Substitute equation 3 into equation 2 to get
(4) Fc = mg tan(b)
You can now set equations 1 and 4 equal to each
other
m(v^2)/r = mg tan(b)
30^2/r = 9.8*tan23
r = 216.35
(v) is the woman's initial velocity, (b) is the angle at which she
leans on the jet ski, and you are solving for the turning radius
(r)
The final answer should be about 216.35
m