A 36 kg skier skis directly down a frictionless slope angled at 13° 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 1.2 m/s2, and (c) increasing at a rate of 2.4 m/s2. Use g = 9.81 m/s2

Question

z4k4r1y4 · Answer

I got:  a) 79.4 N     b) 36.2 N    c) -6.96 N
I'm not sure about (c)

z4k4r1y4 · Answer

fro (a) I combined newton's first and second law for acc=0, and for (b) & (c) I just used Newtons' second law.

anonymous · Answer

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Fd=DRiving force,If
a)velocity is constant$$Fd=Fx=mgsin \alpha=36*9.81*\sin13=79.4Newtons$$
b)increasing at a rate 1.2m/s^2
Using the formula$$Fd-Fx=ma$$
$$Fx=Fd-ma=79.4-(36*1.2)=36.2N$$
c)$$Fx=79.4-(36*2.4)=-7N$$I think it still shows that the direction is up the plane.