Need help on Newton's Law Question and Determining speed

AI Thread Summary
To determine Iceman's speed at the bottom of the 1m ice slide inclined at 20 degrees, it's essential to analyze the forces acting on him, including gravity, normal force, and friction. The net force can be calculated using the equation ΣFnet = m ⋅ anet, where the forces should be resolved into x and y components. A free body diagram is recommended to visualize the forces, particularly placing the x-axis along the incline to simplify calculations. The friction force is determined by the coefficient of kinetic friction and the normal force, which is perpendicular to the slide. The mention of the slide's length as 10.0 x 10^(-8) nm appears to be a typographical error, likely intended to be 10.0 x 10^8 nm.
richvrd1
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My teacher made this question:

Iceman is sliding down a 10.0 x 10^(-8) nm ice that is inclined at 20.0 degrees with respect to the horizontal. Iceman is initially at rest. The coefficient of kinetic friction between iceman's feet and the ice is 0.100. Determine Iceman's speed at the bottom of the ice slide.

What I know:
1)There are 3 forces as he slides down this slide: force gravity going straight down, force normal which is parallel to the slide @ 20.0 degrees, and force friction which is in the opposite direction he slides down.
2)The slide is 1m.
3)ΣFnet= m ⋅ anet ... I then attempted to split it into x and y accordingly where ΣFnetx = m ⋅ anetx &
ΣFnety = m ⋅ anety
4) Force friction is equal to -(μ)Fn
5)Fnety= Fgy + Fn
 
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If you have not done so already, you should draw a free body diagram. And I would recommend drawing your +x axis in the direction of the downward slope of the incline, with your y-axis perpendicular to that. By doing that, you will only have an x component of acceleration, which should simplify the problem. Then the y force components will sum to zero, allowing you to find the normal force, which will allow you to find the friction force.

Seems very strange that the incline length is specified to be 10.0 x 10^(-8) nm. By the way, it looks like it should be +8.
Also, it was probably just misstated but the normal force is perpendicular to the slide, not parallel.
 
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