Iceskating up a Hill: Determining Height with Initial Velocity and Friction

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An iceskater weighing 69 kg glides up a 20-degree incline with an initial velocity of 8.9 m/s and experiences a friction force of 0.97 N. The skater's motion is analyzed using the equations for gravitational force components and friction. The calculated acceleration is 3.34 m/s², leading to a distance of approximately 11.8 m along the incline. When applying the sine function for the incline, the height reached is around 4.1 m, which rounds to 4.0 m. The final calculations confirm that the initial misunderstanding was in the math, not the physics.
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Homework Statement



An iceskater weighing 69kg is gliding up an incline hill at 20 degrees.
How high up does the skater make it when her initial velocity is 8,9m/s and the friction between her skates and the ice is 0,97N.

Homework Equations



mg(y) = m*g*cos(20)
mg(x) = m*g*sin(20)

The Attempt at a Solution


F(friction) = \mu * mg(y)

F\rightarrow = F(f) + F(mg(x))

a=F\divM\rightarrowF\divm=232,7\div69 = 3,34m/s^2

s = (v^2 - v(o)^2) / 2a = 11,8m

sin(20)*11,8=4,05...\approx 4,1m

the answer should be 4,0m. What am I doing wrong?
 
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Physics looks good, maths is off...redo the math: you should get something like 4,02 which rounded to two sig figs is 4,0
 
I see, thanks. I thought my problem was that I was thinking about it all wrong. I redid the math and it checks out.

Appreciate the help!
 
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