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lfwake2wake
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Homework Statement
A 54 kg skier skis directly down a frictionless slope angled at 12° to the horizontal. Choose the positive direction of the x-axis to be downhill along the slope. A wind force with component Fx acts on the skier. What is Fx if the magnitude of the skier's velocity is (a) constant, (b) increasing at a rate of 1.1 m/s2, and (c) increasing at a rate of 2.2 m/s^2
Homework Equations
Fx=M*ax
Fy=M*ay
The Attempt at a Solution
First I need to solve for the weight acting in the x direction. Putting the positive x direction relevant to the motion of the skier, I get:
a. Fx=M*g*cos(12)=517.64 N
b. Since having no net force on an object gives no acceleration, by setting the force of the wind equal to the force of gravity in the x direction, this is achieved.
Fx(wind)=517.64 in the negative x direction
Ftotal=Fxg-Fxw Since Ftotal=0, Fxg=Fxw
c. Now is where I'm having trouble. If it is increasing at a velocity of 1.1 m/s^2, then a=1.1 m/s^2. So to find the acceraltion in x, the net force is divided by the mass, I think.
F=ma ===>>> 517.64 N / 54 kg = 9.5858 m/s^2. So now, I think i need to subtract 1.1 m/s^2 from that answer and multiply again by 54 to find the solution. So 9.5858 +1.1=10.69 m/s^2 * 54kg=577.04 N
d. Same as above, but add 2.2 to 9.5858...636.44 N
I'm not sure if any of this is right. Thanks in advance for the help.